Method and system for allocation of frequency resources on basis of set of coefficients of frequency reuse in cellular communication systems

FIELD: physics, communication.

SUBSTANCE: this purpose the method includes stages of division of the given continuance of time on, at least, two subperiods of time and formation of the frequency resource by means of application of crossly various coefficients of a reuse of frequency by it subperiods of time.

EFFECT: maintenance of allocation of frequency resource in cellular communication.

15 cl, 18 dwg, 3 tbl

 

The technical field to which the invention relates

The present invention relates to a cellular system. More specifically, the present invention relates to a system and method for allocating frequency resources based on a variety of factors reuse of frequencies in a cellular system using multiple access orthogonal frequency division (OFDMA).

Description of the prior art

As a rule, in the cellular system, the same frequency resources can be used in two zones, even when they are located at a certain distance from each other to achieve the rational and efficient use of limited frequency resources. The concept of reuse frequency will be described with reference to Fig. 1, which depicts a schematic representation of the concept of reuse of frequencies in a traditional cellular system.

With reference to Fig. 1, the frequency resource F1 used in the first cell 100 having the radius R, can be used in the second cell 150, having a radius R, which is from the first cell 100 at a distance D. This is called "reuse frequency.

Factor To reuse frequencies obtained when re-using the same frequency resource, then e is th the same frequency band in the K cell elements. Ratio increased re-use of the frequency distance D between cells using the same frequency resource, also increases. In addition, the wave is attenuated in proportion to the distance of propagation, so that the interference from the use of the same frequency resource decreases with the increase of the coefficient reuse frequency. The number of frequencies available in one cell, can be obtained by dividing a full frequency band into factor To reuse frequencies, thus increasing the rate of reuse frequency may adversely affect the efficiency of the entire system. The distribution of the frequency resource in accordance with the ratio To reuse frequencies will be described with reference to Fig. 2A through 2F. In Fig. 2A shows a schematic view illustrating frequency resource allocation, when the coefficient is To reuse frequency is equal to 3 (K=3). With reference to Fig. 2A, if the ratio of reuse frequency is equal to 3, each of the three hundred and distributedfrom the entire frequency band. In Fig. 2B shows a schematic view illustrating frequency resource allocation, when the coefficient is To reuse frequency is equal to 4 (K=4). As shown in Fig. 2B, if the ratio To the Torno use frequency equal to 4, each of the four hundred dividedfrom the full band.

In Fig. 2C shows a schematic view illustrating frequency resource allocation, when the coefficient is To reuse frequency is equal to 7 (K=7). If the coefficient is To reuse frequency is equal to 7, each of the seven hundred dividedfrom the full band.

In Fig. 2D shows a schematic view illustrating frequency resource allocation, when the coefficient is To reuse frequency equalIn this case,from the total bandwidth allocated to each group of three hundred from among all the nine hundred, respectively, thus, the coefficient For reuse frequencyapplicable to each of the nine hundred.

In Fig. 2E shows a schematic view illustrating frequency resource allocation, when the coefficient is To reuse frequency equalFull bandwidth allocated to each group of three hundred of all the twelve hundred, thus, the coefficient For reuse frequencyapplicable to each of the twelve hundred.

In Fig. 2F shows schematics the second image, illustrating the distribution of the frequency resource when the coefficient is To reuse frequency equalAs shown in Fig. 2F, if the coefficient is To reuse frequency equalfrom the total bandwidth allocated to each group of three hundred twenty one cell, so that the coefficient is To reuse frequencyapplicable to each of the twenty one cell.

In the analog cellular system, wireless voice requires a minimum signal-to-noise ratio (SNR). To match the SNR defined minimum distance between the frames. The coefficient reuse frequency is also determined based on the SNR.

In the digital cellular system, the minimum value of SNR can vary depending on the coding rate of error-correcting applied in a wireless line modulation schemes and transmission schemes. In particular, in the communication system, multiple access, code division (CDMA) all satam coefficient reuse of frequency equal to 1, taking into consideration the minimum SNR, the capacity of the system and network design. Since the CDMA communication system applies to all sotam the same frequency band, the ex who keeps cells from each other, the process code expansion/compression of the spectrum. In this way the interference of the adjacent honeycomb average, so the data from the service at the moment cell can be distinguished from other data cells.

The coefficient reuse frequency is an important factor in the system of the cellular packet radio using multiple access orthogonal frequency division (OFDMA). As discussed above, if the ratio of reuse of frequencies K=1, improved system capacity and simplifies network design. The ratio of carrier to interference and noise ratio (CINR) of the signal downlink in a cellular system with a reuse factor of frequency equal to 1, is described below with reference to Fig. 3.

In Fig. 3 shows a schematic representation illustrating CINR downlink in a cellular system using a reuse factor of frequency equal to 1. As shown in Fig. 3, in the Central region 301 cell adjacent to the base station (BS), the intensity of the interference signal having the same frequency band from the neighboring cells does not affect the intensity of the signal downlink, that is, CINR, so that there is a relatively high CINR. However, the edge region 303 cells remote from the BS, is subject to considerable influence from the interference signal having the same frequency band from a neighbour in their hundreds, therefore, there is a relatively low CINR.

When the subscriber terminal (SS) is in the boundary area of the cell 303, if the cellular system provides low bit rate coding, error-correcting scheme and a low-speed modulation, frequency efficiency SS in the border region 303 cell can be reduced, even if SS can normally receive packet data from the BS.

To solve the problems described above, the coefficient For reuse frequency is set at K>1. Even if the ratio of reuse frequency set in K>1, the signal could be reduced in proportion to the distance of wave propagation, so CINR downlink decreases in the direction of the boundary region 303 cell. However, because the interference is very small, CINR downlink relatively high, if the ratio of reuse frequency set in K>1 versus CINR downlink, when the ratio of reuse of frequency equal to 1. This will be described in detail with reference to Fig. 4.

In Fig. 4 shows a graph illustrating the relation between CINR and the distance from the BS, when the cellular system applied factor reuse of frequency equal to 1 (K=1) and greater than 1 (K>1). As shown in Fig. 4, with increasing ratio popcorn the use of frequency frequency efficiency in the boundary area of the cell can be improved. However, since each of the hundreds of uses 1/K of the entire bandwidth, the capacity of the entire system is reduced compared with the system using a reuse factor of frequency equal to 1.

The invention

Thus, the present invention was made to solve the above-mentioned problems occurring in the prior art, and the purpose of the present invention to provide a system and method for allocating frequency resources based on a variety of factors reuse of frequencies in the OFDMA cellular system.

Another objective of the present invention is to provide a system and method for allocating frequency resources through the application of a variety of factors re-use of the frequency corresponding to the States of the subscriber stations (SS) in the OFDMA cellular system, thus increasing system capacity and improving system reliability.

To achieve these objectives, according to the first aspect of the present invention provides a method of allocating frequency resources by means of the transmitter of the cellular communication system, the method includes the steps at which the predetermined time period is divided into at least two sub-periods of time and frequency resources are formed by applying different to the rates of re-use frequencies to poderiam time.

According to the second aspect of the present invention provides a method of allocating frequency resources by means of the transmitter of the cellular communication system, the method includes the steps in which all subcarriers cellular communication system are divided into at least two groups; each group is divided into at least two subgroups according to the number of coefficients reuse frequencies used in the cellular system; and the subgroups are divided into sets of subgroups, respectively, the coefficients reuse frequency; and a specified number of subcarriers selected from each subgroup sets of subgroups, thus forming frequency resources.

According to a third aspect of the present invention provided a system for allocating frequency resources in the cellular system, and the system includes: a transmitter for dividing a predetermined period of time, at least two sub-periods of time and the formation of frequency resources by applying different factors to reuse frequency in payperiod time.

According to the fourth aspect of the present invention provided a system for allocating frequency resources in the cellular system, and the system includes: a transmitter for the separation of all subcarriers in the cellular system is a, at least two groups, dividing each group into at least two subgroups according to the number of coefficients reuse frequencies used in the cellular system, and the subgroups are divided into sets of subgroups, respectively, the coefficients reuse frequency, and selecting a given number of subcarriers of each sub-group of the sets of subgroups, thus forming frequency resources.

According to the fifth aspect of the present invention provides a method of re-use of frequencies within a given period of time the temporary storage area of each base station providing the cell/sector in which the coefficient For reuse is defined so that one frequency band is reused in K cells/sectors, and the method includes the steps of applying reuse factor equal to 1 in the first period of time, which is part of the aforementioned predetermined period of time; and applying a coefficient To reuse in the second period of time, which is the remaining part of the aforementioned predetermined period of time.

Brief description of drawings

The above and other objectives, features and advantages of the present invention will be more visible from the subsequent detailed description and the accompanying hell is, by Mesdames, on which:

in Fig. 1 shows a schematic representation illustrating the concept of the reuse of frequencies in a traditional cellular system;

in Fig. 2A shows a schematic view illustrating frequency resource allocation, when the coefficient is To reuse frequency is equal to 3;

in Fig. 2B shows a schematic view illustrating frequency resource allocation, when the coefficient is To reuse frequency equal to 4;

in Fig. 2C shows a schematic view illustrating frequency resource allocation, when the coefficient is To reuse frequency is equal to 7;

in Fig. 2D shows a schematic view illustrating frequency resource allocation, when the coefficient is To reuse frequency equal

in Fig. 2E shows a schematic view illustrating frequency resource allocation, when the coefficient is To reuse frequency equal

in Fig. 2F shows a schematic view illustrating frequency resource allocation, when the coefficient is To reuse frequency equal

in Fig. 3 shows a schematic representation illustrating CNIR descending lineolate in the cellular system, using the ratio of reuse of frequency equal to 1;

in Fig. 4 shows a graph illustrating the relation between CINR and the distance from the BS, when the cellular system applied factor reuse of frequency equal to 1 (K=1) and greater than 1 (K>1);

in Fig. 5 shows a schematic view illustrating frequency resource allocation based on many factors re-use frequencies in the OFDMA cellular system according to the variant of implementation of the present invention;

in Fig. 6 shows a schematic representation illustrating the procedure for creating a subchannel, based on many factors re-use frequencies in the OFDMA cellular system according to the variant of implementation of the present invention;

in Fig. 7A shows a schematic representation illustrating the procedure for creating a subchannel in the OFDMA cellular system, based on the ratio of reuse of frequency equal to 1, according to the variant of implementation of the present invention;

in Fig. 7B shows a schematic representation illustrating the set of subchannels, as shown in Fig. 7A, distributed satam constituting the OFDMA cellular system according to the variant of implementation of the present invention;

in Fig. 8A shows a schematic representation illustrating the procedure of sosteniendola in the OFDMA cellular system, based on the coefficient reuse frequency K according to the variant of implementation of the present invention;

in Fig. 8B shows a schematic representation illustrating a group of subchannels, as shown in Fig. 8A, distributed to the sectors making up the honeycomb in the OFDMA cellular system according to the variant of implementation of the present invention;

in Fig. 9 shows a schematic view illustrating frequency resource allocation based on many factors re-use frequencies in the OFDMA cellular system according to the first variant implementation of the present invention;

in Fig. 10 shows a schematic representation illustrating the process of allocation of frequency resources based on a variety of factors re-use frequencies in the OFDMA cellular system according to the second variant of implementation of the present invention; and

in Fig. 11 shows a flowchart illustrating the process of allocation of frequency resources on the basis of coefficients reuse frequency in accordance with the condition of the channels of the terminal SS in the OFDMA cellular system according to the second variant of implementation of the present invention.

A detailed description of the preferred option exercise

Variant implementation of the present invention will be described below with reference to the maint is approving the drawings. In the following detailed description, a detailed description is included here known functions and configurations will be omitted, since they can make incomprehensible object of the present invention.

In Fig. 5 shows a schematic view illustrating frequency resource allocation based on many factors re-use frequencies in the cellular system multiple access orthogonal frequency division (OFDMA) according to the variant of implementation of the present invention.

As shown in Fig. 5, if the subscriber terminal (SS) is located in the Central region 501 cell adjacent to the base station (BS), the ratio of carrier to interference and noise ratio (CINR) is relatively high, so the ratio of reuse of frequency equal to 1. If SS is located in the border region 503 cell, the ratio of reuse frequencies more than 1 (K>1) to prevent the reduction CNIR. If SS is moved from the border area 503 cells in the Central region 501 cell, then the distributed SS frequency resource ceases to be greater than 1 (K>1) and becomes equal to 1.

In OFDMA cellular systems, frequency resource allocation is performed in podkalni unit, which includes at least one of subcarriers. Way to create a subchannel, based on many factors red the use of frequencies in the OFDMA cellular system, described here with reference to Fig. 6.

In Fig. 6 shows a schematic representation illustrating the procedure for creating a subchannel based on many factors re-use frequencies in the OFDMA cellular system according to the variant of implementation of the present invention.

With reference to Fig. 6, if the OFDMA cellular system uses N subcarriers, these N subcarriers are divided into G groups. Each of the G groups consists of S subcarriers, so that the following equation is satisfied:

N=SG.

The first sub-channel is created by selecting one subcarrier from each of the G groups. The second sub-channel is created by selecting one subcarrier from each of the G groups, with the exception of the aforementioned subcarrier allocated to the first subchannel. The above procedure can be repeated until all sub-carriers of the G groups will not be allocated to subchannels. As a result, creates a set of S subchannels.

You can also create a new set of S subchannels having subcarriers other than the above subcarriers by varying schemes of selecting subcarriers. The number of sets of S subchannels, comprising mutually different subcarriers is equal toHere, the combination of sub-carriers forming the sub-channel will be called "combination carrier". In the subsequently described and, the set ofthe subchannel selected from amongsets of S subchannels, defined asand the m-th sub-channel from a set ofthe subchannel is defined asHere n=[0,and m=[0, S-1]. S subchannelforming one and the same set ofsub-orthogonal to each other. Thus, the subcarriers forming each of the S sub cannot overlap with each other.

In addition, the subchannelforming mutually different set of subchannels, aligned without ensuring orthogonality between them. Thus, the subcarriers forming mutually different subchannels may overlap each other. In addition, C setsthe subchannel selected from amongsets of S subchannels. Here, if a given sub-channel is selected respectively from each of the C setsof subchannels, the number of subcarriers having the characteristics overlap, can be uniform. As a result, the total number of subcarriers with signs of overlap between the two sets of subchannels is proportional to the number of subchannels. As a result, the set of subchannels POPs is an by selecting subcarriers from among sets of S subchannels. Through various schemes, you can create C sets of subchannels with mutually different combinations of subcarriers and subcarriers representing homogeneous characteristics overlap.

Below you will learn how to control subchannel in the OFDMA cellular system c coefficient reuse of frequency equal to 1.

First, when the ratio of reuse of frequency equal to 1, all subcarriers in a given cell of the cellular communication system OFDMA (all subchannels) can be used in adjacent channels.

If each cell uses a set of subchannels having the same combination of subcarriers (that is, if each cell uses the same A), interference can occur in each subchannel, depending on the state of the channel. Accordingly, it is impossible to predict the state of the channel when measured at the moment the channel is used in the next period of time.

Way to create a subchannel, when the ratio of reuse of frequency equal to 1 will be described below with reference to Fig. 7A and Fig. 7B.

In Fig. 7A shows a schematic representation illustrating the procedure for creating a subchannel in the OFDMA cellular system, based on the ratio of reuse of frequency equal to 1, according to a variant implementation of the program of the present invention.

With reference to Fig. 7A, if the OFDMA cellular system uses N subcarriers, C setsthe subchannels can be created from N subcarriers through a variety of schemes of selecting subcarriers. In Fig. 7B shows a schematic representation illustrating a set of subchannels corresponding to Fig. 7A, distributed satam forming the OFDMA cellular system according to the variant of implementation of the present invention.

With reference to Fig. 7B, satam forming the OFDMA cellular system, distributed C sets Aof subchannels. Each sub-channel from C sets Athe subchannels are orthogonal to other subchannels in the same set of subchannels, while relative to the subchannels of the other sets of subchannels is homogeneous characteristics overlap. Accordingly, if C sets Aof subchannels allocated to each cell, a component of interference from neighboring cells can be averaged due to the homogeneous characteristics of overlapping subcarriers. Thus, if the number of resources used by the neighboring cells, has not changed, it is possible to maintain the reliability of the information about the state of the channel, measured in a given unit of time. Thus, the OFDMA cellular system can effectively control subchannel, based on the coefficients is and re-use frequencies equal to 1.

However, despite the fact that the value mistaway interference can be averaged CINR may be reduced from components interference with neighboring cells. In particular, the CINR is significantly reduced in the boundary area of the cell.

To provide coverage of a wireless cellular communication system to SS, which is in the boundary area of the cell, it is possible to apply a very low coding, error correction, and modulation schemes with low order modulation. However, very low coding, error correction, and modulation schemes with low order modulation can reduce the efficiency of use of frequency bands and, thus, significantly reduce the transmission rate for SS located in the boundary region of the cell.

Below, the average speed of the SS and the average transmission rate in accordance with the radius of the cell in the OFDMA cellular system, based on the ratio of reuse of frequency equal to 1 will be described with reference to Table 1. The values shown in Table 1, were obtained by checking the simulation method using the scheme of planning circular algorithm, in which for the channel environment taken into consideration as long-term fading and short-term fading. That is, the cell/sector is divided into many con is intricacy circles, which do not overlap and have the specified area. Then calculated the average transmission rate of each SS placed in each of the concentric circles. After that, the average transmission rate of each SS is calculated to obtain the average transmission rate for each radius of each concentric circle). In the table the radius of the cells sorted in ascending order of the radius of the cell.

The average transmission rate for each radius can be determined as a function of the transmission rate of each SS relative to the size of the cell. Average transfer rate is shown in Table 1 are average values of transmission rates of SS placed in concentric circles that gradually decrease, while the SS moves towards the boundary area of the cell or sector. For this reason, the average transmission rate corresponding to the circle having the largest size, less than the average transmission rate close to the Central area of the cell/sector, due to the elements with interference from neighboring hundredth/sector of the OFDMA cellular communication system that uses the ratio of reuse of frequencies equal to 1.

Table 1
The radius of the cell0,10,20,3 0,40,50,60,70,80,91,01,0˜
The average speed SS1,000,900,750,640,500,400,260,230,170,170,13
The average speed for radius0,260,600,830,891,000,900,630,490,370,240,25

As described above, taking into account elements of interference from neighboring cells/sectors, the OFDMA cellular system uses the coefficient reuse frequency K. Thus, the use of frequency resources, affecting neighboring cell/sector is limited. For example, the OFDMA cellular system with a reuse factor of frequency K uses the K frequency bands, each of which is different from others. Alternatively, the system logically divides the subcarriers included in one frequency band, K groups of subcarriers.

The procedure to create a subchannel in the OFDMA cellular system, based on the coefficient reuse frequency K, will be described below with reference to Fig. 8A and 8B.

In Fig. 8A showing the schematic but the image illustrating the procedure for creating a subchannel in the OFDMA cellular system, based on the coefficient reuse frequency K according to the variant of implementation of the present invention. Of subcarriers forming one frequency band is divided into K groups of subcarriers and the coefficient reuse frequency is controlled on the basis of the K groups of subcarriers. In Fig. 8A coefficient reuse frequency is equal to 3 (K=3).

S subchannel forming a specified setsub-divided into three exceptional groups of subchannels defined asIn Fig. 8B shows a schematic representation illustrating a group of subcarriers, such as shown in Fig. 8A, distributed by sectors that form the honeycomb cellular OFDMA.

With reference to Fig. 8B, when the ratio of reuse of frequency equal to 3, three groups of subchannelsallocated to each sector of the cell. In the ideal case, mistowa/intersector interference happens rarely, so the average speed of SS, which is in the boundary area of the cell or sector may increase. However, the resources allocated to each cell or sector, reduced to 1/3, thus, the capacity of the cell or sector reduced.

The average transmission rate in accordance with the laws the AI with radius cell in the OFDMA communication system, based on the coefficient reuse of frequency equal to 1 and 3, will be described below with reference to Table 2.

The values shown in Table 2, were obtained by checking the simulation method using the scheme of planning circular algorithm, in which for the channel environment taken into consideration as long-term fading and short-term fading. The radii of the cells in the table sorted in ascending order of the radius of the cell.

Table 2
The radius of the cell0,10,20.30,40,50,60,70,80,91,01,0˜
The rate of repeated use of the frequency "1"113267378411467428306242181118123
The coefficient reuse frequency "3"90220314320401379326268222152164

As can be seen from Table 2, the use of coefficients is and re-use frequencies equal to 3, gives the best transmission speed in the boundary area of the cell or sector and the worst rate in the Central area of the cell adjacent to the BS, compared to the OFDMA cellular system that uses the ratio of reuse of frequency equal to 1. This is because the component of interference from neighboring cells or sectors is reduced in the Central region due to slow fading. In addition, since the OFDMA cellular system using a reuse factor of frequency equal to 3, can use 1/3 of the resources, the capacity of the system also decreases.

The method of application of the coefficients reuse of frequency equal to 1 and K to increase the efficient use of bandwidth and system capacity in OFDMA cellular system will be described below. As described above with reference to Fig. 5, SS, located in the Central area of the cell, is relatively weak interference. These SS located in the Central region of the honeycomb, can work on the basis of the ratio of reuse of frequency equal to 1. In contrast, SS, located in the boundary area of the cell, can work with K>1 to reduce the interference component acting on SS from neighboring cells or sectors. That is, if the OFDMA cellular system applies the coefficients on the Torno use frequency 1 and K, the interference imposed on the SS from neighboring cell/sector can be reduced in the boundary area of the cell/sector and system capacity can be improved in the Central area of the cell.

However, if the cellular system uses OFDMA coefficients reuse frequency 1 and K without their physical distinction, the result is a relatively large component interference. As a result, may decrease SS CINR, with a coefficient of reuse frequency K, and his work will significantly deteriorate. To solve the problems described above, between the frequency resources having mutually different coefficients reuse frequency, ensures orthogonality.

Method for allocating frequency resources based on a variety of factors re-use of frequencies by the first and second variant implementation of the present invention will be described below. In the first embodiment of implementation of the present invention, various coefficients reuse frequencies are applied to mutually different time fields.

According to the second variant of implementation of the present invention, various coefficients reuse frequencies are applied to mutually different frequency resources.

First, the method for allocating frequency resources in the cell system St is zi OFDMA, on the basis of many factors reuse frequency in the first embodiment of implementation of the present invention will be described with reference to Fig. 9.

In Fig. 9 shows a schematic representation illustrating the distribution of frequency resources based on a variety of factors re-use frequencies in the OFDMA cellular system according to the first variant implementation of the present invention.

As shown in Fig. 9, according to the scheme of allocation of the frequency resources of the current version of the implementation, the specified time domain, that is, one frame 900 is divided into a field 903, using the ratio of reuse of frequency equal to 1, and field 905, using the coefficient reuse frequency K in this time domain. In field 903, using the ratio of reuse of frequency equal to 1, all cells/sectors of the OFDMA cellular communication system using mutually different sets of subchannels in such a way that all cells/sectors can be managed with reuse factor equal to 1. In field 905, using the coefficient reuse frequency K, each cell/sector uses the same set of subchannels in such a way that all cells/sectors can be controlled by the ratio of reuse of frequency equal to K. for Example, different sets of podina the s is divided into K exclusive groups, so one of them could be used.

The procedure of allocation of the frequency resources based on a variety of factors re-use frequencies in the OFDMA cellular system according to the second variant of implementation of the present invention will be described below with reference to Fig. 10.

In Fig. 10 shows a schematic representation illustrating a procedure for allocating frequency resources based on a variety of factors re-use frequencies in the OFDMA cellular system according to the second variant of implementation of the present invention.

With reference to figure 10, if the OFDMA cellular system uses N subcarriers, these N subcarriers are divided into G groups. Here, each of the G groups consists of S subcarriers, so that the following equation is satisfied:

N=SG.

In addition, each of the G groups is divided into two subgroups, and the subgroups include Ssubcarriers and Ssubcarriers.

First, by selecting one subcarrier from each of the G sub-groups created the first sub-channel. The second sub-channel is created by selecting one subcarrier from each of the G subgroups, except as described subcarrier allocated in the first sub-channel. The above procedure can be repeated until all subcarriers of G p is dgroup will not be allocated to subchannels. As a result, creates a set of Sof subchannels. In addition, as mentioned above, it is also possible by means of variation of the scheme of selecting subcarriers to create a new set Afrom C subchannel having subcarriers other than those described above. This subchannels new set Aorthogonal to each other in the same set of subchannels, while relative to the subchannels of the other sets of subchannels are homogeneous characteristics overlap. Set Aof subchannels allocated for each cell/sector so that the cell/sector can be controlled by the ratio of reuse of frequency equal to 1.

Then, by selecting one subcarrier from each of the G groups, including Ssubcarriers, and generates the first sub-channel. The second sub-channel is created by selecting one subcarrier from each of the G subgroups, except subcarrier allocated in the first sub-channel. The above procedure can be repeated until all sub-carriers of the G subgroups will not be allocated to subchannels. As a result, creates a set of Sof subchannels. The subchannels are divided into K exclusive groups of subchannels and distributed to each of the K SOT/sectors, so that satisfactory can be controlled by the ratio of reuse frequency K. For example, because the subchannels using the ratio of reuse of frequencies equal to 1, and subchannels using the coefficient reuse frequency K, include mutually different subcarriers, the interference can be prevented, even if the coefficients of the re-use of frequency equal to 1 and K, are used simultaneously.

Table 3 shows the validation results of the method of simulation run allocation of the frequency resources based on a variety of factors re-use frequencies in the OFDMA cellular system according to the first and second variants of implementation of the present invention.

Check the way the simulation was performed on the three sectors and nineteen sectors by applying the average rate sector of the Central cell to the sectors and satam, while each sector has used the model of an isotropic antenna and a real antenna. In addition, the result of verification by simulation method was obtained when the attenuation factor of the line, equal to 3.8. Check the way the simulation was performed with one-pass model, taking into account the attenuation and, in addition, applying the standard deviation of the shadowing is 8 dB, if shading is presented.

When used, the coefficient re-use the project for a frequency equal to 3, the time resource and frequency resource are supported so that the interference among the three sectors is minimized. In addition, the coefficients reuse frequency 1 and 3 are distributed in the OFDMA cellular system with equal respect. That is, the area ratio of reuse of frequency equal to 1, is identical to the plot of the ratio of reuse of frequency equal to 3, in the time domain when S=Sused in the frequency domain.

Table 3
The ideal antennaReal antennaR-ANT Attenuation, Shadowing
The rate of repeated use of the frequency "1" (bit/s/Hz)1,701,070,97
The rate of repeated use of the frequency "1", "3" (bps/Hz)to 1.861,191,08
Increase transfer rate11,011,211,1

As shown in Table 3, when the coefficients of the re-use of frequency equal to 1 and 3 used in the OFDMA cellular system according to the first and second variants of implementation of the present invention, the system p is poizvoditelnosti increases by approximately 10%, whereas the average transmission rate (bit/Hz/s) in each sector, in comparison with system performance of the OFDMA cellular communication system that uses only the ratio of reuse of frequency equal to 1.

As mentioned above, the frequency resources with different coefficients reuse frequencies distributed during the transfer of the real custom package. Frequency resource (OFDM symbols or subchannels)having a given coefficient re-use frequencies are allocated for the transmission of user packets depending on the channel status of the receiver. Here, the channel state of a receiver includes an interference in the receiver or parameters related to interference. According to the present invention the state of the receiver channel is correlated with CINR. Since most interference can occur when the ratio of reuse frequency is equal to 1, the distribution of frequency resources can be accomplished through the use of CINR in relation to the ratio of reuse of frequency equal to 1. The distribution of frequency resources in accordance with the state of the receiver channels can be performed so as to send a custom packet to a receiver having the greatest CINR, first allocated frequency resource with the coefficient of the m reuse frequency, equal to 1. In conclusion, the frequency resource with the highest rate of repeated use of the frequency is allocated for transmission of the user packet to a receiver that has the lowest CINR.

In Fig. 11 shows a flowchart illustrating a procedure for allocating frequency resource, which is distributed on the basis of its coefficients reuse frequency in accordance with the condition of the SS channels in OFDMA cellular system according to the second variant of implementation of the present invention.

With reference to Fig. 11, the status information transmitted BS on the feedback channel from each SS (step S1101), and the BS allocates frequency resources with mutually different coefficients reuse frequency according to the state information of the channels SS (step S1102). In addition, the BS sorts SS respectively, of the frequency resources with different frequency resources distributed by the SS to transmit data at step S1102 (step S1103) and data transmission to the SS through the inclusion of SS in the queue according to the scheduling algorithm (step S1104).

As mentioned above, according to the present invention, the frequency resources are allocated based on many factors re-use frequencies in the OFDMA cellular system so that the CINR is not reduced in the boundary area of the cell, thereby improving system performance. In addition, according to the present invention, the set of coefficients reuse frequencies are applied according to the channel status SS so that could increase the capacity of the system and can improve operational reliability.

Although this invention has been shown and described with reference to certain preferred ways of its implementation, specialists in the art it will be clear that it is possible to make various changes in form and detail without departure from the essence and scope of the invention as defined by the accompanying claims.

1. The allocation of frequency resources by means of the transmitter of the cellular communication system, the method includes the steps are carried out

the separation of the transmitted frame in the time domain for at least two sub-periods of time; and

the distribution of frequency resources by receivers through the use of different factors of re-use frequencies to each of the above-mentioned at least two podpriatov time.

2. The method according to claim 1, in which the distribution of frequency resources by receivers through the use of different factors of re-use frequencies to each of the above-mentioned at least two podpriatov time who will win the stage, where: distribute these frequency resource to the receiver corresponding to the transmitter by applying coefficients reuse frequency according piped feedback from the receivers to the transmitter status information channels.

3. The method according to claim 2, in which when allocating a frequency resource to the receivers, the rate of repeated use of the frequency applied to the frequency resource, the distributed receivers with information about the status of the channels that reflect the worst channel condition is greater than the rate of repeated use of the frequency applied to the frequency resource, the distributed receivers with information about the status of the channels that reflect the best channel condition.

4. The allocation of frequency resources by means of the transmitter of the cellular communication system, the method includes the steps are carried out

the division of all subcarriers of a cellular communication system in at least two groups;

the separation of each of these groups on at least two subgroups according to the number of coefficients reuse frequencies used in the cellular system;

the separation of these subgroups on the sets of subgroups respectively used coefficients reuse frequency; and the choice of the certain number of subcarriers of each subgroup sets of subgroups, thus, allocating frequency resources and receivers.

5. The method according to claim 4, in which the distribution of frequency resources and receivers contains a stage at which: allocate frequency resources on the receiver corresponding to the transmitter by applying coefficients reuse frequency according piped feedback from the receivers to the transmitter status information channels.

6. The method according to claim 5, in which when allocating a frequency resource to the receivers, the rate of repeated use of the frequency applied to the frequency resource, the distributed receivers with information about the status of the channels that reflect the worst channel condition is greater than the rate of repeated use of the frequency applied to the frequency resource, the distributed receivers with information about the status of the channels that reflect the best channel condition.

7. The system for allocating frequency resources in a cellular system containing

the transmitter to separate the transmitted frame in the time domain for at least two sub-periods of time and allocation of the frequency resources and receivers by applying various factors to reuse frequencies to these poderiam time.

8. The system according to claim 7, which contains a number of receivers for which peredachi channel feedback information about the state of their channels to the transmitter.

9. The system of claim 8, in which the transmitter distributes the receivers frequency resources by applying the coefficients reuse frequency according piped feedback from the receivers to the transmitter status information channels.

10. The system according to claim 9, in which the rate of repeated use of the frequency applied to the frequency resource, the distributed receivers with information about the status of the channels that reflect the worst channel condition is greater than the rate of repeated use of the frequency applied to the frequency resource, the distributed receivers with information about the status of the channels that reflect the best channel condition by means of the transmitter.

11. The system for allocating frequency resources in a cellular system containing

the transmitter for the separation of all subcarriers of a cellular communication system in at least two groups, separating each of these groups on at least two subgroups according to the number of coefficients reuse frequencies used in the cellular system, the separation of these subgroups on the sets of subgroups respectively used coefficients reuse frequency, and selecting a given number of subcarriers of each subgroup sets of subgroups, thus distributing chaston the e resources and receivers.

12. The system according to claim 11, which additionally contains a number of receivers for channel transmit feedback information about the state of their channels to the transmitter.

13. System according to clause 12, in which the transmitter distributes the receivers frequency resources by applying the coefficients reuse frequency according piped feedback from the receivers to the transmitter status information channels.

14. The system of item 13, in which the rate of repeated use of the frequency applied to the frequency resource, the distributed receivers with information about the status of the channels that reflect the worst channel condition is greater than the rate of repeated use of the frequency applied to the frequency resource, the distributed receivers with information about the status of the channels that reflect the best channel condition by means of the transmitter.

15. A way to reuse frequency in a given period of time the temporary storage area of each base station providing the cell/sector in which the factor is To reuse frequency is defined so that one frequency band is reused in cells/sectors, comprising stages

application of the coefficient of reuse of frequency equal to 1 in the first period of time, which is part of mentions is wow specified period of time; and

applying the coefficient To reuse frequency in the second time period, which is the remaining part of the aforementioned predetermined period of time.



 

Same patents:

FIELD: physics, communication.

SUBSTANCE: base station packs and transmits the conferring with the information on the next base stations, a containing special field of a flag for restriction of the information on the next base stations, and the reserved field, and also this conferring does not join the iterated information on the next base stations depending on the value set in a special field of the flag, thus, raising efficiency of transmission. The portable terminal accepts from base station the conferring with the information on the next base stations, checks the accepted conferring and then updates the identifier of the functional according to the value set in a special floor of a flag.

EFFECT: pinch of efficiency of transmission at loading decrease on the alarm system.

8 cl, 2 dwg, 4 tbl

FIELD: physics, communication.

SUBSTANCE: invention gives technologies for reaction to overlapping requirements in networks of a wireless communication which includes a transmit-receive of data from a sending device through a wireless communication network, these data transmission correspond to linking with a sending device and occur within the reserved part of a resource of communication, the requirement of cross noises which includes allocation of a resource of communication for the next device which is overlapped with the reserved part, on the basis of this detection is found out, in an expedient the notice on a sending device goes, the notice specifies presence of overlapped transmissions in the reserved part of a resource of communication.

EFFECT: decrease in cross noises of transmissions in wireless communication networks.

43 cl, 8 dwg

FIELD: communications.

SUBSTANCE: through conversion to specific information, contained in a channel, user equipment (UE) establishes a point-to-point connection with a base transceiver station (BTS) without interrupting reception of multimedia broadcast batch service (MBMS), which is the engineering solution.

EFFECT: new channel for controlling direct exchange line.

16 cl, 3 dwg

FIELD: communications systems.

SUBSTANCE: proposal is given of a method and device for generating a physical layer packet (PL) with variable length. Many security level packets (SL) can be multiplexed to a single PL-packet, so as to increase efficiency. SL-packets can vary their lengths. In one version, SL-packets of a different format for different users are joined in capsules, which a PL-packet. The shortest packets are meant for users with bad channel conditions or requiring less data, determined by use and associated requirements for quality of service (QoS). In one of the versions for modifying the header structure there are single-address and multiple user packets. An alternative version provides for modified sets of speeds, a mechanism for identification of an acknowledgment indicator ("АСК") from a single user packet or a multiplexed packet (delayed "АСК"). Amplitude manipulation for an "АСК"-channel is in contrast to bipolar manipulation, used in IS-856, and/or multivalent interpretation DRC.

EFFECT: increased efficiency through varying packet length.

21 cl, 19 dwg

FIELD: wireless communication.

SUBSTANCE: present invention pertains to a method of carrying out fast handover by a subscriber station (SS) in a broadband wireless communications system, consisting of a base station (BS), exchanging data with a SS, and at least one BS, neighboring a service BS. The SS receives downlink signals from the service BS and neighboring BS, measures the arrival time difference of the downlink signal, received from the service BS, and the downlink signal received from the neighboring BS, and sends the measured time difference to the service BS.

EFFECT: effective range control in a wireless broadband communications system.

53 cl, 11 dwg, 4 tbl

FIELD: communications systems.

SUBSTANCE: proposal is given of a method of compressing control information for an up-link in a wireless communication system, where a mobile user station scans neighboring base stations upon request by a service base station and sends information on the neighboring base stations to the service base station. In this method, the service base station sends a message with notice of neighboring base stations, which includes an identifier, of at least one neighboring base station, about which the service station intends to obtain information and an identifier of the above mentioned neighboring base station. The mobile user station then scans the channel, transmitted by at least one neighboring base station, and sends the scanning result together with the index of that neighboring base station to the service base station.

EFFECT: reduced unproductive expenses.

13 cl, 4 dwg, 1 tbl

FIELD: radio engineering.

SUBSTANCE: equipment and method for positioning in sector for wireless communication device and data transmission from base station to wireless communication device through signalling channel in wireless communication network without allocated data access channelisation. When base station is ready to transmit data through signalling channel to wireless communication device, at first it sends routing table update message to wireless communication device. Wireless communication device sends response back to base station, not starting any traffic channelisation procedure. The response is delivered with sector position information to base station. After response is received base station transmits data to signalling channel in sector where wireless communication device is connected.

EFFECT: internet protocol (IP) data package transmitting to signalling channel without transmitting of IP data packages to sectors where target wireless communication device is not connected, thus avoiding network flooding with unnecessary signalling messages.

22 cl, 4 dwg

FIELD: radio engineering.

SUBSTANCE: invention refers to cellular telephone communications. Method of relaxed service transmission includes the first control channelisation through network between the first base station controller (BSC) and the first base transceiver station (BTS). Besides method includes the second control channelisation through network between the second BSC and the second BTS. Dial-up between mobile station (MS) and the first BTS is accompanied with evidence of MS signal reception from the second BTS that is sent to the first BSC. As respond to evidence start signal is transmitted from the first BSC to the second BTS. And as respond to reception of start signal to the second BTS, additional traffic, associative connected with dial-up, is directed between MS, the second BTS and the first BSC without transmission of the additional traffic through the second BSC.

EFFECT: every BTS is capable to connect through numerous communication lines with many BSC, and every BSC is capable to connect through numerous communication lines with many BTS.

24 cl, 4 dwg

FIELD: radio engineering.

SUBSTANCE: invention refers to identification of transmitters for signals received by terminal. In order to evaluate transmitter of this received signal, candidate list of transmitters which could transmit this signal is made out. Besides coverage area is detected to be used for received signal. This coverage area is area where terminal can receive signal to be identified. Then predicted power for each candidate transmitter is evaluated, e.g. using route and coverage area loss prediction model. Predicted powers for candidate transmitters are compared (directly or relatively) to measured power of received signal. Candidate transmitter with (direct/relative) predicted power closest to (direct/relative) measured power is considered to be that one transmitted this signal. Distribution delays can be predicted and used for transmitter identification as well.

EFFECT: estimation of terminal location.

27 cl, 12 dwg

FIELD: radio engineering.

SUBSTANCE: method and device for wireless one-way channel location within transmitting of multimedia multipoint connection using base parameter configuration of wireless one-way only channel for rapid location of wireless one-way only channel, when mobile terminal travels between cells, are offered. Using parameter configuration of wireless one-way only channel for certain service within multipoint connection, applying base configuration so that parameters of protocol and channel, the same or with equal values are determined for every cell, various cells within communication system in which certain point-to-point connection service is rendered, can configure objects of wireless protocol, channels and wireless one-way only channel simultaneously, using the same parameters values.

EFFECT: method allows for minimal delay of wireless one-way only channel location and data loss during transmission service, thus keeping network resources and improving reception performance through smooth combination.

79 cl, 8 dwg

FIELD: radio communications.

SUBSTANCE: proposed method intended for single-ended radio communications between mobile objects whose routes have common initial center involves radio communications with aid of low-power intermediate transceiving stations equipped with non-directional antennas and dropped from mobile object, these intermediate transceiving drop stations being produced in advance on mentioned mobile objects and destroyed upon completion of radio communications. Proposed radio communication system is characterized in reduced space requirement which enhances its effectiveness in joint functioning of several radio communication systems.

EFFECT: reduced mass and size of transceiver stations, enhanced noise immunity and electromagnetic safety of personnel.

1 cl, 7 dwg, 1 tbl

FIELD: radio communications.

SUBSTANCE: proposed method intended for data transfer from mobile object to stationary one residing at initial center of common mobile-object route using electronic means disposed on stationary and mobile objects involves radio communications with aid of low-power intermediate transceiving stations equipped with non-directional antennas and dropped from mobile object, these intermediate transceiving drop stations being produced in advance on mobile object. Proposed radio communication system is characterized in reduced space requirement which enhanced its effectiveness in joint functioning with several other radio communication systems.

EFFECT: reduced mass and size of transceiver stations, enhanced noise immunity and electromagnetic safety of personnel.

2 cl, 6 dwg

FIELD: radio communications.

SUBSTANCE: proposed method intended for data transfer to mobile object from stationary one residing at initial center of mobile-object route using electronic means disposed on stationary and mobile objects involves radio communications with aid of low-power intermediate transceiving stations equipped with non-directional antennas and dropped from mobile object, these intermediate transceiving drop stations being produced in advance on mobile object. Proposed radio communication system is characterized in reduced space requirement which enhances its effectiveness in joint functioning with several other radio communication systems.

EFFECT: reduced mass and size of transceiver stations, enhanced noise immunity and electromagnetic safety of personnel.

2 cl, 6 dwg, 1 tbl

FIELD: radio communications.

SUBSTANCE: proposed method for single-ended radio communications between mobile objects whose routes have common initial center involves use of low-power intermediate transceiving stations equipped with non-directional antennas and dropped from mobile objects. Proposed radio communication system is characterized in reduced space requirement and, consequently, in enhanced effectiveness when operating simultaneously with several other radio communication systems.

EFFECT: reduced mass and size, enhanced noise immunity and electromagnetic safety for attending personnel.

2 cl, 7 dwg, 1 tbl

FIELD: radio communications.

SUBSTANCE: proposed method intended for data transfer to mobile objects from stationary one residing at initial center of common mobile-objects route using electronic means disposed on stationary and mobile objects involves radio communications with aid of low-power intermediate transceiving stations equipped with non-directional antennas and dropped from first mobile object. Proposed radio communication system is characterized in reduced space requirement which enhances its effectiveness in simultaneous functioning of several radio communication systems.

EFFECT: reduced mass and size of transceiver stations, enhanced noise immunity and electromagnetic safety of personnel.

2 cl, 7 dwg, 1 tbl

FIELD: radio communications.

SUBSTANCE: proposed method intended for data transfer to mobile objects from stationary one residing at initial center of common mobile-objects route using electronic means disposed on stationary and mobile objects involves radio communications with aid of low-power intermediate transceiving stations equipped with non-directional antennas and dropped from first mobile object, these intermediate transceiving drop stations being produced in advance on first mobile object. Proposed radio communication system is characterized in reduced space requirement which enhances its effectiveness in joint functioning with several other radio communication systems.

EFFECT: reduced mass and size of transceiver stations, enhanced noise immunity and electromagnetic safety of personnel.

2 cl, 7 dwg, 1 tbl

FIELD: radio communications.

SUBSTANCE: proposed method for single-ended radio communications between mobile objects having common initial center involves use of low-power intermediate transceiver stations equipped with non-directional antennas and dropped from mobile objects. Proposed radio communication system is characterized in reduced space requirement and, consequently, in enhanced effectiveness when operating simultaneously with several other radio communication systems.

EFFECT: reduced mass and size, enhanced noise immunity and electromagnetic safety of personnel.

2 cl, 7 dwg, 1 tbl

FIELD: radio communications.

SUBSTANCE: proposed method intended for data transfer to mobile objects from stationary one residing at initial center of common mobile-objects route using electronic means disposed on stationary and mobile objects involves radio communications with aid of low-power intermediate transceiving stations equipped with non-directional antennas and dropped from first mobile object, these intermediate transceiving drop stations being produced in advance on first mobile object and destroyed upon completion of radio communications between mobile and stationary objects. Proposed radio communication system is characterized in reduced space requirement which enhances its effectiveness in joint functioning with several radio communication systems.

EFFECT: reduced mass and size of transceiver stations, enhanced noise immunity and electromagnetic safety of personnel.

2 cl, 7 dwg, 1 tbl

FIELD: radio communications engineering; digital communications in computer-aided ground-to-air data exchange systems.

SUBSTANCE: proposed system designed to transfer information about all received messages irrespective of their priority from mobile objects to information user has newly introduced message processing unit, group of m modems, (m + 1) and (m + 2) modems, address switching unit, reception disabling unit whose input functions as high-frequency input of station and output is connected to receiver input; control input of reception disabling unit is connected to output of TRANSMIT signal shaping unit; first input/output of message processing unit is connected through series-connected (m + 2) and (m + 1) modems and address switching unit to output of control unit; output of address switching unit is connected to input of transmission signal storage unit; t outputs of message processing unit function through t respective modems as low-frequency outputs of station; initialization of priority setting and control units, message processing unit clock generator, and system loading counter is effected by transferring CLEAR signal to respective inputs.

EFFECT: enhanced efficiency due to enhanced throughput capacity of system.

1 cl, 2 dwg

FIELD: radiophone groups servicing distant subscribers.

SUBSTANCE: proposed radiophone system has base station, plurality of distant subscriber stations, group of modems, each affording direct digital synthesizing of any frequency identifying frequency channel within serial time spaces, and cluster controller incorporating means for synchronizing modems with base station and used to submit any of modems to support communications between subscriber stations and base station during sequential time intervals.

EFFECT: enhanced quality of voice information.

12 cl, 11 dwg

Up!