ADAPTATION OF DATA TRANSFER SPEED IN OFDM SYSTEM IN PRESENCE OF NOISES Russian patent published in 2009 - IPC H04B7/02 

FIELD: information technologies.

SUBSTANCE: method consists in adaptive change of used subcarriers and speed of data transfer on these subcarriers in OFDM communication system, which uses frame structure of signal and one of P possible speeds of data transfer in the presence of noises in signal band and under specified target level of bit error probability, due to grouping of every frame in units on transmitting side of initial information bits, their coding, transfer of the first frame at minimum speed, separation of OFDM subcarriers into groups, data of affected groups on subcarriers is not transmitted, on receiving side subcarriers of OFDM signal are detected, which are affected by noises, block error (BLER) frequency is analysed in current and previous frames, probability of block error of current frame is compared to the first threshold, by result of comparison with threshold, decision is made on necessity of repeated transfer, average bit error BER is calculated for different speeds of current frame transfer, average probability of bit error is compared to the second threshold and the third threshold, and speed of transfer is selected for the next frame, unaffected groups of subcarriers, speed of the next frame data transfer, and also necessity to repeat data of current frame are transmitted in service message along feedback channel from receiving side to transmitting side.

EFFECT: higher throughput in the presence of noise in signal band.

12 cl, 4 dwg