Method and device for signal demodulation

FIELD: radio engineering and communications.

SUBSTANCE: invention relates to communication. Versions of present invention disclose a method and a device for signal demodulation, which enable to reduce effect of Doppler frequency shift on data transmission rate. During demodulation of a received radio-frequency signal sent by a base station after receiving a reference clock signal provided by PMU device, additionally, it is necessary to determine speed of a mobile terminal, wherein Doppler frequency shift, generated when mobile terminal receives radio-frequency signal sent by base station, is determined in accordance with speed of movement, and received radio-frequency signal, transmitted by base station, is demodulated in accordance with said reference clock signal and value of Doppler frequency shift.

EFFECT: since during demodulation of a radio frequency signal transmitted by a base station, Doppler frequency shift is taken into account, demodulation accuracy is high and, consequently, problem related with low accuracy of demodulation and low rate of transmitting data in presence of Doppler frequency shift is solved.

13 cl, 12 dwg

 



 

Same patents:

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to communication. In at least one embodiment, a wireless communication device implements a method to receive reference information on a first set of subcarriers; generate first channel quality estimates in the frequency domain, based on the received reference information; calculate a signal power to time delay ratio profile for the first set of subcarriers; and determine second channel quality estimates either by extrapolation, based on the first channel quality estimates or as an average of the first channel quality estimates, depending on the delay variation in the signal power to time delay ratio profile.

EFFECT: obtaining channel quality estimates for given subcarriers in an OFDM signal, based on measurements of a reference signal (RS) or another known signal, derived for another set of subcarriers.

15 cl, 8 dwg

FIELD: radio engineering, communication.

SUBSTANCE: receiver in a bus node of a bus network, in particular an EIB network. A receiver in a node of a bus network is connected to a to a bus line (Bus+, Bus-) for receiving a signal transmitted thereon, said signal consisting of bit pulses, comprises a differential amplifier having a first input for reference voltage (E1) and a second input (E2) for voltage carrying the signal, wherein the signal at the output appears only and only if the absolute value of voltage at the second input is greater than the absolute value of the reference voltage at the first input, and a feedback resistance is connected between the output and the first input of the differential amplifier.

EFFECT: optimisation with respect to sensitivity, behaviour and noise-immunity.

6 cl, 3 dwg, 1 tbl

FIELD: electricity.

SUBSTANCE: invention relates to electrical engineering, to a transmitting cascade in a bus assembly of a bus network, mainly in a bus assembly of EIB-network, which is connected to a bus line (Bus+, Bus-), for generation of a bit signal that corresponds to a transmitted signal that has a sequence of transmitted pulses and that consists of an active pulse for each transmitted pulse, which has duration Δt=t1-t0, with that, t0 indicates the beginning of the active pulse, and t1 - at the end of active pulse, and depth Ua of pulse, and an equalising pulse following after the active pulse, with circuit (A) for generation of active pulse, optionally, with circuit (B) for generation of the equalising pulse and at least one control circuit (C) that outputs transmitted signal (Usend) at least to circuit (A) for generation of active pulse. Pulse depth (Ua) of active pulse is set by the specified reference voltage (Uref) that is independent of the value of constant voltage component of a bit signal.

EFFECT: possible replacement of active elements with passive components.

6 cl, 6 dwg

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to digital radio communication systems. A method of estimating parameters of a radio signal in a radio receiver, received from a transmitter, which denotes defined symbols in the data sequence of said radio signal, using the given alternative modulation for said defined symbols, wherein the method includes the following steps: identifying a plurality of said defined symbols in the data sequence, which are transmitted with higher reliability than the rest of the symbols in the data sequence; demodulating said defined symbols transmitted with higher reliability first in order to generate soft pilot symbols, and using the soft pilot symbols as known symbols in order to estimate parameters of the received radio signal, wherein the soft pilot symbols have modulation of a lower order than modulation of a higher order, used for the rest of the symbols in the data sequence.

EFFECT: improved data throughput of the communication system.

16 cl, 13 dwg

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to high-speed transmission of information over a wire line. A double-channel line driver, having a first line driver, a second line driver, a charge pump, and a control logic circuit connected to the first line driver and the second line driver and configured to disable the charge pump when both a first control signal associated with the first line driver and a second control signal associated with the second line driver indicate a charge pump disable state. A network component comprising at least one processor configured to implement the method, comprising receiving a first control signal and a second control signal, disabling a charge pump when both the first control signal and the second control signal indicate a charge pump disable state, and operating the charge pump to boost a voltage when the first control signal, the second control signal, or both indicate a charge pump active state.

EFFECT: low power consumption.

20 cl, 10 dwg

FIELD: radio engineering, communication.

SUBSTANCE: disclosed is a method, an apparatus and a computer-readable medium for receiving a signal, which includes components consisting of a plurality of cells, channel estimation from a received signal using one or more channel estimation schemes, removing the component signal using the estimated channel from the received signal to generate a processed signal and detecting a residual signal in the processed signal.

EFFECT: further improvement of LTE technology.

56 cl, 16 dwg

FIELD: radio engineering, communication.

SUBSTANCE: transmitter transmits a set of soft pilot symbols with higher reliability than the remaining symbols in the sequence by modulating the soft pilot symbols with a lower order modulation such as scaled quadrature phase shift keying (QPSK) or scaled binary phase shift keying (BPSK) while modulating the remaining symbols with a higher order modulation such as 16QAM or 64QAM. The transmitter shares the modulation type and location (time/frequency/code) of the soft pilot symbols with a receiver. Unlike traditional fixed pilots, the soft pilots still carry some data. Additionally, the soft pilots are particularly useful in establishing the amplitude reference essential in demodulating the higher order modulation symbols. In another version, soft pilot symbols are inserted by low-level puncturing of channel encoded bits and replacing the punctured bits with known bit patterns.

EFFECT: simple receiver, improved efficiency thereof, eliminating the error effect when demodulating data.

43 cl, 13 dwg

FIELD: radio engineering, communication.

SUBSTANCE: techniques for transmitting and receiving data with spatial interference mitigation in a wireless network are described. In one design of transmitting data with spatial interference mitigation, a first station (e.g., a cell) may receive spatial feedback information (SFI) from a second station (e.g., an interfered UE) that is not communicating with the first station. The second station may also receive precoding information from a third station (e.g., a served UE). The first station may send a data transmission to the third station based on the precoding information and the SFI in order to reduce interference for the second station. In one design, the SFI may include spatial nulling information. The first station may send the data transmission based on the spatial nulling information to steer the data transmission in a direction away from the second station.

EFFECT: achieving good efficiency even in the presence of powerful base stations not participating in servicing.

40 cl, 12 dwg

FIELD: radio engineering, communication.

SUBSTANCE: pilot signals are received from multiple basic stations or sectors in a time domain, received pilot signals from a time domain are converted into a frequency domain, multiple pilot signals are identified from converted pilot signals, the identified multiple pilot signals are converted from a frequency domain into a time domain. From the converted multiple pilot signals they identify a pilot signal from one of many basic stations or sectors by means of suppression of in-channel interference from many pilot signals from other basic stations or sectors from many basic stations or sectors, and a channel is assessed in a time domain with the help of the identified pilot signal.

EFFECT: higher accuracy of channel assessment.

19 cl, 11 dwg

FIELD: information technology.

SUBSTANCE: in the method encoding data using two pairs of orthogonal sequences, formation of encoding premable using two pairs of additional orthogonal sequences involves transmitting a first sequence corresponding to the first pair using one phase and simultaneously transmitting the first sequence of a second pair using a quadrature phase, transmitting a second sequence corresponding to the first pair using one phase and simultaneously transmitting the second sequence of the second pair using a quadrature phase, transmitting the resultant signal obtained using quadrature modulation to the transmitting medium.

EFFECT: cutting time required for calculating filtration coefficients to reduce overloading of communication systems with data.

2 cl, 4 dwg

FIELD: electrical engineering.

SUBSTANCE: concept of user power supply (current loads RL) through two pairs of data transmission lines of local network is characterized by method and user power supply device (current loads RL) though two pairs of data transmission lines of local network (LAN) featured that to provide power voltage selection of power source circuit device equipped with two electronic inductors (D1/D2, D3/D4) is used for every pair of data transmission line and to provide self-symmetrizing of circuit device both outputs and both leads of electronic inductors (D1/D2, D3/D4) are connected to each other.

EFFECT: cost effective space distribution.

7 cl, 3 dwg

FIELD: communications.

SUBSTANCE: invention pertains to communication technology and can be used in wireless communication lines with many antennae. For receivers of systems with many inputs and a single output (MISO) a pilot signal transmitted in one direction is preferred, and for receivers of systems with many inputs and many outputs (MIMO), usually the pilot signal should be transmitted in different directions. In one system of transmitting a pilot signal the first set of T scaled pilot symbols is generated using the first instruction vector and transmitted, for example, continuously from T transmitting antennae, where T>1. If the MIMO receivers are supported by a communication system, then at least T-1 additional sets of T scaled pilot symbols are generated, at least, using T-1 additional instruction vectors and transmitted from T transmitting antennae. The instruction vectors are designed for different, for instance, orthogonal directions. Each MISO receiver can evaluate its MISO-channel, based on the first set of scaled pilot symbols. Each MIMO receiver can evaluate its MIMO-channel, based on the first and additional sets of scaled pilot symbols.

EFFECT: increased efficiency of transmitting pilot signals in a system with many antennae.

52 cl, 11 dwg

FIELD: physics, communications.

SUBSTANCE: invention concerns communication technology and claims methods of obtaining eigen vectors on the basis of guiding reference signal, used in spatial processing. Guiding reference signal is a pilot signal transmission over one eigen mode of MIMO channel in symbol period, using guiding vector for this eigen mode. Guiding reference signal is used in singular value evaluation and matrix and in left-hand eigen vector matrix of channel response matrix. Matrix with squared columns can be obtained via QR-expansion, minimum square error calculation or polar decomposition. Matrix evaluations can be used in coordinated filtering of data transfer received over first communication line, and in spatial processing of data transfer over second communication line (for reverse first and second communication lines).

EFFECT: obtaining eigen vectors on basis of guiding reference signal.

23 cl, 6 dwg

FIELD: physics; communications.

SUBSTANCE: present invention pertains to digital wireless communication systems, specifically to evaluation of channel characteristics and interference levels in such systems. Evaluation of channel parameters and interference levels in multiple user systems with several carriers (OFDM) with variable parameters is done at the same time. To carry out evaluation, several data symbols and separate pilot symbols are transmitted on channel. The initial evaluated value of interference level is then chosen. That value, together with received pilot symbols, is used for first channel evaluation. The first channel evaluation is used to determine the new corrected interference level which, in turn, is iteratively used for updating the value of the first channel evaluation. Iteration continues, until the iteratively updated value of interference level and channel reach preset limits. Data symbols and the current updated channel value are then used for second channel evaluation. The minimum root-mean-square error method is then used and channel evaluation and noise scattering in the OFDM system are iteratively updated.

EFFECT: simultaneous evaluation of channel parameters and interference level in multiple user systems with several carriers (OFDM) with variable parameters.

21 cl, 4 dwg, 2 tbl

FIELD: information technologies.

SUBSTANCE: only the frequency pilot-code or the time-and-frequency pilot-code is appointed to each transmitter for use at only temporary by pilot-signal transmission. The pilot-codes can be pseudorandom, orthogonal codes and-or codes with cyclic detrusion. For reception of an estimate of the channel for the transmitter using the time-and-frequency pilot-code, consisting of only temporary code and only the frequency code, the receiver multiplies a set of the accepted figures for each continuance of a figure by a set of code values for only frequency code for the purpose of reception of a gang of the found out figures and carries out inverse discrete Fourier transform (IDFT) of the set of the found out figures for the purpose of reception of an initial estimate of the pulsing performance. The receiver carries out comparison of a code by set of initial estimates of the pulsing performance output for set of continuances of a figure, with only temporary code for the purpose of reception of a definitive estimate of the pulsing performance for the demanded transmitter. The receiver maintains the first L taps of the channel and zeros other taps of the channel where L represents the expected length of the channel.

EFFECT: maintenance of an estimate of the channel in the presence of set of transmitters.

68 cl, 12 dwg

FIELD: physics, communication.

SUBSTANCE: invention is related to data transmission, namely, to temporal filtering for reduction of excessive delay in systems with orthogonal frequency division multiplexing with orthogonal frequency division multiplexing (OFDM, FDM). To reduce harmful effects of excessive delay duration, temporal filtering has been used in channel assessment. Temporal filtering is carried out, when pilot-signals shifted relative to each other are available.

EFFECT: reduction of harmful effects of excessive duration of delay.

15 cl, 8 dwg

FIELD: physics, radio.

SUBSTANCE: invention may be used in reverse channel of radio communication systems of multiple access with orthogonally frequency-multiplexed signals (OFDMA), in particular, in compliance with standard 802.16. Method for assessment of reverse channel of OFDMA system consists of two stages. At the first stage correction of pilot symbols is carried out with the help of regression, and at the second stage, by means of interpolation of the first order of pilot symbols, correction of modulated data is carried out. Compared to interpolation, regression is less sensitive to accuracy of pilot signals assessment than interpolation. However, regression is more efficient for monotonous curves. Therefore, in stated method adaptive regression window is introduced, size of which is selected so that sequence of pilot signals in window is, first, monotonous, and second is sufficient for assessment of channel at specified ratio of signal/noise. Invention makes it possible to increase accuracy of communication channel assessment and therefore, to improve noise immunity of signals reception in reverse channel of radio communication systems of multiple access with orthogonal frequency multiplexed signals.

EFFECT: makes it possible to increase accuracy of communication channel assessment and therefore, to improve noise immunity of signals reception in reverse channel of radio communication systems of multiple access with orthogonal frequency multiplexed signals.

3 cl, 7 dwg

FIELD: physics; communication.

SUBSTANCE: invention relates to methods and systems for improving channel evaluation in a wireless communication system. The method involves reception of a wireless signal, which contains several multipath components, and obtaining N channel evaluations, where N is any positive integer greater than one. Each channel evaluation is associated with its own multipath component. Obtaining N channel evaluations involves filtering the received wireless signal using a matched filter, which is matched with the pulse characteristic of the filter of the transmitter baseband; N delays are evaluated; the output signal of the matched filter is descrambled using pseudorandom noise, through which N descrambled signals are obtained; each of the N descrambled signals is correlated with a reference signal to obtain N channel evaluations; a multipath correlation matrix is calculated; a noise covariance matrix is calculated; the said matrices are used to reduce interference effects between several multipath components in N channel evaluations; interference effects between multipath components are reduced based on N channel evaluations.

EFFECT: design of a channel evaluation method, which minimises effects of multipath interference.

19 cl, 10 dwg

FIELD: information technologies.

SUBSTANCE: invention is related to data transfer from microcircuit chip to microcircuit chip, which uses method of current mode instead of generally accepted methods of differential transfer of voltage mode signals. Current pulse is introduced into one of two transfer wires based on signal value subject to transfer (for instance, logical "0" or "1") by driver in transmitting microcircuit chip. Current pulse is accepted as differential current signal in receiving unit in receiving microcircuit chip. Differential current signal is transformed by current comparators into differential signal of low span voltage. Differential voltage signal may be detected by receiver of operational amplifier, which produces according value of signal.

EFFECT: reduction of consumed power and electromagnet noise.

8 cl, 6 dwg

FIELD: information technologies.

SUBSTANCE: method and device for evaluating transfer function h(t) if communication channel contains steps of creating the data di sequence having the built cdi part associated with at least two codes w0, w1, in which correlation function Acode of the built cdi part with one of the two codes w0, wi is characterised with maximum value at k=0 and less than maximum value at k≠0; creating cj sequence of signal elements, which has Tc period of signal elements, as data sequence expanded with the enlarging sequence Si which is N long; creating com (t) = co(t + mNTc) at m=0, 1, …, M by means of correlation of the received signal r(t) with the enlarging sequence Si, where received signal r(t) contains sequence cj of signal elements, which has been used for communication channel; and creating evaluation of transfer function of communication channel, as combinations com(t) and dm at m=0, 1, …, M.

EFFECT: effective evaluation of transfer function of communication channel when the received signal has losses in a short enlarging code.

54 cl, 11 dwg

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