The method of radio communication in a wireless local area network transceiver and the device

 

The invention relates to wireless local area networks (WLAN) consisting of a set of transceiver devices (SRD) users and enables simultaneous scanning of the antenna beam in different directions PPU, in the reception mode, and transmission omnidirectional signal as the calibration signal and the data packet is one of the PPU, in the transfer mode detection signal PPU, in the reception mode, and the subsequent orientation of their antenna beams per source. The detection of the received signal and the orientation of the antenna beams provide for the reception of the calibration signal. The foam includes at least one directional antenna with controlled directivity, a switching unit, switch reception and transmission, receiver, transmitter and controller. In the device additionally introduced the block identification signal. The technical result is to increase the reach or range of the WLAN users, increasing the data transfer speed, improved quality and reliability of communication, the ability to transmit information simultaneously to multiple users on the network. 2 S. and 19 C.p. f-crystals, 9 Il.

The invention of the relative is adowanie for sending and receiving various kinds of information.

Currently, wireless local area networks are becoming more widespread in the field of Informatics and videographic communication and distribution of data and other information between multiple users on the same site, for example between being in the same building as personal computers, laptop computers, printers and other users, without limiting the mobility of these devices. The transmission of information using WLAN allows you to reduce the cost of creating the network, eliminating the need to strip wires. A network of this type can also be used in cases where it is difficult or impossible to lay the connecting wires, as well as in cases related to the lack of outlets for local area networks due to architectural limitations. WLAN is an ideal solution for organizations, which often changes the location of users. In existing WLAN radio is usually carried out according to known international standards, such as IEEE 802.11b.

A number of known methods of radio communication in the WLAN based on the use for transmission and reception of signals from the radiation Omni-directional antenna receiving the (ad hoc) to transmit information simultaneously to arbitrary number of users, including changing its location.

Thus, the method of wireless data exchange system between multiple wireless stations [3] includes the broadcast of one of the stations that will transmit the data synchronization message, and the determination of those stations from a set, which is designed to transfer data; the translation of these selected stations during the broadcast synchronization messages in the mode of operation at relatively high power level; the translation of the other stations, which is not designed to transfer data to the standby mode at a relatively low level of power; the transmission of all data for selected stations and returning them after taking into standby mode at a relatively low power level.

There is a method allows to economize on resource self-contained power sources, users of the network. At the same time, the use of Omni-directional radiation signal imposes a limitation on the reach or range, which is determined mainly by the radiation power transmitting device and the sensitivity of its receiver, which the WLAN users usually cannot be greatly increased. In addition, the known method does not provide the second interference and also because of the effect of the fading signal (fading).

Known transceiver device designed for use by WLAN users, containing the transceiver is equipped with an omnidirectional antenna and is connected to the bus connected to the processor, the memory and the timer standby mode, in turn, connected to the auxiliary power source connected to the transceiver via a switch connected to the timer standby mode and the control circuit power [3].

Known transceiver device allows you to increase the service life of a standalone power source network users. At the same time using the device omnidirectional antenna limits the reach or range, which is determined mainly by the radiation power transmitting device and the sensitivity of its receiver, which in a mobile WLAN users, receiving power from an independent source, usually can not be increased significantly. In addition, the known transmitting device does not provide sufficient reliability of radio communication because of the possible occurrence at the point of signal reception of the phenomenon of multipath interference, and the effect of samiran is and antennae diversity and implement this method transceivers, where information take on the antenna providing the best signal quality [4, 5, 6].

For example, in [6] described by way radio for use in communication networks, in which the receiver has multiple antennas. The choice of antenna providing the best signal reception, carried out during reception of the preamble of the transmitted data packet.

The known method, allowing to minimize the effects of fading, keeps the same limitations on the reach or range, which are inherent in the methods that use Omni-directional radiation for transmission and reception of information.

Known transceiver device [6] for use in a WLAN, comprising multiple antennas connected to the switch, whereby during transmission of the preamble of the data packet to include the radio antenna with the best performance.

Known transceiver device allows to minimize the effects of fading, but retains the same restrictions on the range of devices that use Omni-directional antenna for transmission and reception of information.

The closest to the essential features of the claimed of izobretatelny calibration signal one transceiver device to the second transceiver device, receiving this signal is also Omni-directional antenna; then the definition of multiple directional antennas of the second device that provides the best conditions of the reception signal, the transmission of the second transceiver device using the selected antenna calibration signal used to select the best quality signal reception of a directional antenna of the first transceiver device, and further radio communication with selected when transmitting calibration signals of directional antennas of the first and second transceiver devices [7].

Using the known method prototype directional radiation transceiver devices helps to ensure sufficient reliability of radio communications due to reduce the influence of multipath interference and fading. At the same time establishing radio communication at the first stage using Omni-directional radiation patterns does not allow to increase the reach or range of the WLAN users compared with methods that use the principle of diversity antennas. In addition, when using the prototype method before transmission of the data packet requires two transmit calibration signal that ovality time a packet increases with the number of these users.

The known method is the prototype implemented using a transceiver devices [7] , each of which includes at least one directional antenna and an omnidirectional antenna, which is connected through the switch unit antennas with a movable contact of the switch mode of acceptance, the stationary contacts of which are connected respectively with the receiver input and transmitter output. The first receiver is connected to the first input of the controller, and the second receiver output is connected to the input unit of measurement quality signal, the output of which is connected to the second input of the controller. The first output controller connected to the switch unit antennas, the second output controller connected to the first input of the transmitter, and the third output of the controller is connected to a second input of the transmitter. The controller has a two-way communication with the memory unit and the user interface.

Known transceiver device prototype allows to increase the reliability (quality) of the radio communication between two users by reducing the effects of multipath interference and fading. But these advantages have to pay the increase in the transmission time of each data packet and the lack of capacity in order to increase the reach or range of the WLAN users compared with devices using spaced antenna, as in the first stage of communication transmission and reception are using Omni-directional antennas.

The task of the claimed invention is to provide such a method of communication in a wireless LAN, and the development of such a transceiver device, which, while preserving the dignity of prototypes, would increase the reach or range of the WLAN users, as well as to increase the data rate or other information to improve the quality and reliability of communication to transmit information simultaneously to multiple users on the network, including mobile, while reducing the transmission time.

The problem is solved in that in the method of radio communication in a wireless local area network consisting of a set of transceiver devices, perform the following operations: simultaneous scanning of the antenna beam in different directions transceiver LAN devices that are in the receiving mode, and the Omni-directional transmission signal as the calibration signal and the data packet is one of the transceiver devices on the network, in the transmission mode; when the scan signal transceiver ustroystva calibration signal; subsequent reception of one or more data packets in the direction in which the focused antenna beam.

In the inventive method, the scanning can be done in different ways: in the azimuthal direction, elevation angle, azimuth direction and the elevation angle at the same time. You can also step-by-step scanning by switching the antenna directional diagram. Step-by-step scanning can be done in a pre-defined part of the radio space with the best reception condition, and around radioprotective, for example, in increments of 45o, 60o, 90o, 120oor 180o. Other scan types, in addition to the above.

Scanning and orientation of the antenna beams of the transceivers in the direction of the signal source can be repeated during the transmission of each data packet in order to respond quickly to changing conditions of the signal, in particular in the case of mobile network users.

When the reception signal to produce recognition for subsequent orientation of the antenna beam transceiver in the direction of the signal source.

The orientation of the antenna beams premobilization energy parameters of the received signal, for example, a maximum signal strength value or the maximum value of the ratio of received signal level to noise level. The value of the energy parameter of the received signal can be measured at different polarization signal and to receive the data packet when the polarization signal in which the value of the energy parameter takes the maximum value.

It is also advisable during reception of the data packet to measure at least one of the power parameters of the received signal, such as signal strength or signal-to-noise ratio, and a decrease below a certain threshold to resume scanning.

As the calibration signal can be used in the preamble of the transmitted data packet.

To avoid collision of signals before transmission of the data packet, it is desirable to pre-scan radioprotective, for example, in the azimuth direction and elevation angle within 360oor the azimuth direction and the elevation angle within a hemisphere or sphere, depending on the location of users on the network.

After completing the transfer of the transceiver, how great the task is also solved using a transceiver device for use in a wireless LAN, includes directional antenna with controlled directivity, means for said antenna in Omni-directional mode, the mode directional scanning and stationary directional mode and additionally contains means for identifying the received signal, including the calibration signal is designed to switch the above-mentioned antenna of the above-mentioned mode directional scanning in the above-mentioned fixed directional mode in the direction mentioned received signal.

Means to operate the antenna in the above modes may include: means, responsive to a user command to transmit an omnidirectional signal containing the calibration signal, a tool designed to maintain the antenna in the directional mode of scanning in the absence of the calibration signal, and means, responsive to a user command to cancel the operation of the funds destined for the maintenance of the antenna mode directional scanning.

Transmitting-receiving device for use in a wireless LAN may be made in the form of devices, including at mennoti, switch reception and transmission, receiver, transmitter, power quality measurement signal, the controller and added the block identification signal. The antenna is connected through the switch unit pattern with the first input/output switch of acceptance, the output of which is connected to the receiver input and the second input is connected with the output of the transmitter. The output of the receiver is connected to the first input of the controller, to the input of the unit of measurement of signal quality and to the input of the block identification signal output unit of measure of signal quality is connected with the second input of the controller, the output of block identification signal is connected to the third input of the controller, the first controller output is connected to the switch unit pattern, the second output controller connected to the transmitter input and the third output controller connected to the user.

Antenna with controlled directivity pattern may have a very different implementation. For example, the transceiver device may be equipped with one antenna with two or more emitters with directional diagrams, together overlapping not less than 360oin the azimuthal direction or angle of elevation, or dia is about the elevation angle.

Transceiver device can also be done with multiple antennas with single or multiple emitters with directional diagrams, together with the overlying 360oin the azimuth direction and the elevation angle or directional diagrams, together with the overlying hemisphere or sphere on the azimuth direction and the elevation angle.

For example, the transceiver device may be equipped with one antenna with three or six emitters with directional diagrams, together with the overlying hemisphere on the azimuth direction and the elevation angle.

Transceiver device can also be done with three or six antennas with single emitters with directional diagrams, together with the overlying hemisphere on the azimuth direction and the elevation angle.

Transceiver device may be equipped with five antennas with single emitters with directional diagrams, together overlapping area on the azimuth direction and the elevation angle.

Transceiver device may be provided with at least two antennas with a single slocate the field in the azimuth direction and the elevation angle.

You can use the transceiver device and other known embodiments of antennas with controlled directivity.

Simultaneous scanning radio space network users that are in the receive mode, the antenna directional diagram and transfer omnidirectional calibration enable signal, unlike the prototype method, performing the transmission and reception of the calibration signal is Omni-directional antennas to increase the reach or range, and increase the speed of transmission of data or information, to improve the quality and reliability of communication at the same prototype power of the transmitted signal. Further transmission omnidirectional radiation provides simultaneous reception of its many users, while the transition in the way the prototype implements the transmit-receive directional antennas allows to transfer only one user in the "user-to-user (point-to-point), and to transmit this information to multiple users, you must repeat all the operations of reception-transfer of the corresponding number of times, which significantly increases prodolzhitelnost not to interrupt the scan in case of arrival outside signal and thereby avoid loss of information, transmitted to the user at the time of receipt of unwanted signal.

Organization of information transmission by using a directional and Omni-directional antennas used in communications between the mobile transceiver device, in particular between the mobile part, cordless phone, and a stationary transceiver device, for example a base station, cordless phone [8]. However, in contrast to the claimed invention, in the known method, the base station transmits information of the antenna, in partial radioprotective which is one mobile transceiver device equipped with an omnidirectional antenna. If there are multiple mobile transceiver devices located at various points in the radio space, the base station has to transmit in almost Omni-directional mode, thus the way the radio will not differ from the method of communication using the Omni-directional antennas in this way the disadvantages.

The claimed invention is illustrated graphics, where: Fig. 1 illustrates schematically the operation of the antennas WLAN transceiver devices before radio contact; Fig. 2 is; in Fig.3 shows antenna WLAN transceiver devices during transmission of information of Fig. 4 illustrates the operation of antennas WLAN transceiver devices after the end of the session the radio of Fig. 5 shows an example of possible positions (a, b, C, d, e, f, g, h) of the antenna directional diagram of transceiver device of Fig.6 shows a timing chart of process orientation antenna transceivers on the example of a WLAN in accordance with IEEE 802.11, where: Tsfield synchronization; Tor- the total time the orientation of the antenna; Tmsthe time measurement signal; Tswthe time of switching of the antenna; Topt- the last time the switching of the antenna, which antenna is the best position;
in Fig.7 shows the operation modes of the antenna transceiver devices in the process of radio communication;
in Fig. 8 shows a functional diagram of the inventive radio devices operating in the receiving mode;
in Fig. 9 shows a functional diagram of the inventive transceiver device operating in transmission mode.

The method of radio communication in a wireless LAN can be implemented using a transceiver devices the antenna unit 2, consisting of at least one directional antenna 3 with a pattern that is controlled by block 4 switching pattern. Structurally, the antenna unit 2 can be performed in a variety of ways, for example: in one of the antenna 3 at least two emitters with directional diagrams, together overlapping not less than 360oin the azimuthal direction or angle of elevation; as one antenna 3 at least three emitters (for example, with four or six emitters) with directional diagrams, together with the overlying hemisphere or sphere on the azimuth direction and the elevation angle. The antenna unit 2 can also be done at least with the above two antennas 3, having at least one emitter with directional diagrams, together overlapping not less than 360oin the azimuthal direction or angle of elevation. As an example in Fig. 8 and Fig.9 shows a variant of the antenna unit 2 with four directional antennas 3 with single emitters. The unit 2 may be performed at least three of the said antennas having at least one emitter Xu and angle of elevation. Other structural embodiments of the antenna unit 2. Unit 4 switching pattern connected to the first input/output 5 switch 6 acceptance. Output 7 switch 6 of reception and transmission is connected to the input of the receiver 8, and the second input 9 of the switch 6 is connected to the output of the transmitter 10. The output of the receiver 8 is connected to the first input of the controller 11, to the input unit 12 to measure the quality of the signal and to the input of block 13 of the identification signal. The output unit 12 to measure the quality of the signal is connected to the second input of the controller 11, to the third input of which is connected the output of block 13 of the identification signal 10. The first output of the controller 11 is connected to the unit 4 switching pattern, the second output controller 11 is connected to the input of the transmitter 7, and the third output of the controller 11 is designed to connect with the user 14 for receiving and/or transmitting information.

The method of radio communication in a wireless LAN (WLAN), including users 14, 15, 16...N, each of which is equipped with a transceiver device 1, as follows.

Before the session (see Fig. 1) radio communications all users 14, 15, 16...N WLAN carry out scanning radio space antennas 3, the functional is 5), angle of elevation and azimuth direction and the elevation angle, covering the hemisphere or the entire sphere of radio space. Scanning can be done in various ways: step-by-step scanning, including a pre-defined half of the radio space with the best reception condition, in increments of 45o, 60o, 90o, 120o, 180oby electronic switching pattern and other known techniques. After the decision by any user (e.g., 15) to transmit data, it listens to the broadcast scanning directional antenna 3 radioprotective to resolve collisions. If radioprotective freely, the antenna 3 user 15 unit 4 switching pattern (see Fig. 8) translate in Omni-directional mode, the first input/output 5 switch 6 reception-transmission connected to the output of the transmitter 10 and produce the transmission of the calibration signal and data (see Fig.2). Other users 14, 16. ..N network at this time continue to scan radio space antennas 3, operating in a directional mode. In this mode, it looks for the source of the calibration signal. As only those users who use the block 12 of the measuring signal quality measure is one of the energy parameters of the signal (for example, the signal level or the ratio of signal level to noise level) at different positions of the beam 3. Additionally the measurement of the energy parameter can be performed at different polarization signal. The measurement results can be in the controller 11, which produces a control signal to the antenna 3 in the direction corresponding to the best or the specified quality of the received signal, then the above users to receive data from the receiver 8 are received in the controller 11 (see Fig.3).

Modes of operation of the antenna 3 of transceivers 1 user 15, the transmitting data, and the user 14, 16...N taking these data, shown in Fig.7. In the case of reducing the magnitude of one of the power parameters of the received signal is below a specified threshold, the user 14, 16...N, the receiving signal, resume scanning. After the transmission antenna 3 user 15 via the switching unit 4, the pattern is switched to the scan mode, the first input/output 5 switch 6 receive mode-transmission connected to the input of the receiver 8, and the network returns to the original with the standards: IEEE 802.11, IEEE 802.1 la, IEEE 8 02.11 b and ISO 8802-11, HIPELAN type 2. In such a WLAN transmit data packets. At the beginning of each package there is a mandatory part (preamble), intended for the receiver 8 and determine the start information of the parcel. The preamble consists of two fields: synchronization field and a pointer field to the beginning of the information package (Start Frame Delimiter). The preamble is always transmitted with a minimum speed of 1 Mbit/s, which corresponds to the maximum distance coverage. The sync field in case of a short preamble has a duration of 56 μs and was used as a calibration signal for orientation to the source of the directional antenna 3, which in this example could take 16 possible positions. For implementing the method was used antenna, a directivity pattern which is switched electronically (Fig.5). At the time of reception of the synchronization field receiver 8 users, the receiver must perform certain actions, the total duration of 47 ISS. Thus, the total time Torthat can be used for orientation of the antenna 3, is 9 μs. In the worst case, this time is necessary to produce 15 level measurement signal and the scan algorithms and search for the maximum of one of the power parameters of the received signal). The switching time of the beam 3 is bounded below by switching the PIN diodes and is equal to 100 NS. Timing diagram of the process orientation of the antenna 3 shown in Fig.6. As the scanning speed allows you to direct the antenna 3 to the source signal during the preamble, using the proposed method, there are no differences from the protocols of the above standards. It should be emphasized that the acceptance data package shall antenna 3 with a directional graph having a high gain. This allows you to expand the area of sustainable receiving, by increasing the radius of coverage at a speed of 11 Mbps, up to the zone in which without the use of the method it was possible to carry out a radio communication with a speed of 1 Mbit/s

SOURCES of INFORMATION
1. U.S. patent 6026303, IPC H 04 Q 7/00, 2000.

2. U.S. patent 6028853, IPC H 04 J 3/06, 2000.

3. U.S. patent 6192230, IPC H 04 7/14, 2001.

4. U.S. patent 5546397, IPC H 04 7/04, 1996.

5. U.S. patent 5828658, IPC H 04 Q 7/00, 1998.

6. U.S. patent 5748676, IPC H 04 To 1/10, 1998.

7. EP 1063789, IPC H 04 7/04, 2000.

8. WO 96/22646, IPC H 04 B 7/26, 1996.3


Claims

1. The method of radio communication in a wireless local area network consisting of a set of primape rudawski devices mentioned network, in the reception mode, and transmission omnidirectional signal as the calibration signal and the data packet is one of the transceiver devices mentioned network that is in transmission mode, reception with said scanning signal transceiver device and the subsequent orientation of their antenna beams in the direction mentioned transceiver device that is in transfer mode, is carried out at the time of reception of the calibration signal, and the subsequent reception of one or more of the above-mentioned data packets in the direction in which the focused antenna beam.

2. The method according to p. 1, characterized in that said scanning is performed in the azimuthal direction and/or angle of elevation.

3. The method according to p. 1, wherein the implementing step-by-step scanning.

4. The method according to p. 3, characterized in that the step-by-step scanning is carried out in a pre-defined part of the radio space with the best reception condition.

5. The method according to p. 1, characterized in that the scanning is carried out by switching the antenna directional diagram.

6. The method according to p. 1, characterized in that the scanning and orientation of the antenna beams of the transceivers in the Villa of each data packet.

7. The method according to p. 1, characterized in that when scanning to measure at least one of the power parameters of the received signal from the transmitting-receiving devices in the transmission mode, while the orientation of the antenna beams transceivers operate in the direction corresponding to the best or to the preset value of at least one of the measured energy parameters mentioned received signal.

8. The method according to p. 7, characterized in that, as mentioned energy parameter measured received signal level or the level of the received signal to noise level.

9. The method according to p. 1, characterized in that during the reception of the data packet is measured at least one of the power parameters of the received signal from the transmitting device to transmit mode, and when it decreases below a certain threshold resume scanning.

10. The method according to p. 9, characterized in that, as mentioned energy parameter measured received signal level or the level of the received signal to noise level.

11. The method according to p. 1, characterized in that after the end of the lane is hypoxia directions.

12. The method according to p. 1, characterized in that before the beginning of the packet-data pre-scan radioprotective to avoid collision of signals.

13. The method according to p. 1, characterized in that, as mentioned calibration signal using a preamble of a transmitted data packet.

14. The method according to p. 1, characterized in that when receiving the above-mentioned signal to produce recognition.

15. Transmitting-receiving device for use in a wireless local area network including at least one directional antenna with controlled directivity, the switch unit pattern, the switch of reception and transmission, the receiver, the transmitter, the unit of measurement of signal quality, the block identification signal and the controller, while the antenna is connected through the switch unit pattern with the first input/output switch of acceptance, the output of which is connected to the receiver input and the second input is connected with the output of the transmitter, the receiver output is connected to the first input of the controller, to the input of the unit of measurement of signal quality and to the input of the block identification signal output unit of measure of signal quality is connected with the second input of the controller, to rigid switching pattern, the second output of the controller is connected to the input of the transmitter, and the third output controller is intended for connection with a device designed to receive and/or transmit information.

16. Transceiver device according to p. 15, characterized in that is provided with at least one of the mentioned antenna of the at least two emitters with directional diagrams, together overlapping not less than 360° in the azimuth direction and elevation angle.

17. Transceiver device according to p. 15, characterized in that is provided with at least one of the mentioned antenna of the at least two emitters with directional diagrams, together with the overlying field in the azimuthal direction or angle of elevation.

18. Transceiver device according to p. 15, characterized in that is provided with at least one of the mentioned antenna at least three emitters with directional diagrams, together with the overlying hemisphere on the azimuth direction and the elevation angle.

19. Transceiver device according to p. 15, characterized in that provided with at least two of the mentioned antennas with single emitters with directional diagrams, sovakia the device according to p. 15, characterized in that is provided with at least three of the mentioned antennas with single emitters with directional diagrams, together with the overlying hemisphere on the azimuth direction and the elevation angle.

21. Transceiver device according to p. 15, characterized in that provided with at least two of the mentioned antennas with single emitters and at least four mentioned antennas with at least two emitters with directional diagrams, together overlapping area on the azimuth direction and the elevation angle.

 

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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

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