Rate adaptation in an OFDM system the presence of interference

摘要

1. A method of rate adaptation in a OFDM system the presence of noise, comprising adaptively changing subcarriers used and the data rate on those sub-carriers in the OFDM communication system that uses the signal frame structure and one of P possible data rates in noisy environments in the band signal and a predetermined target level, bit error probability, by executing the following operations: at the transmitting storonepered modulation and coding original information bits of each frame are grouped into plaques ki of L pieces and coded, resulting in each block are added by checking bits, the first frame is transmitted at the minimum speed V; signal subcarriers OFDM are divided into J groups of N adjacent subcarriers in the group, data on subcarriers affected groups not performed; power unused subcarriers distributed proportionately among the used subcarriers, so that the transmitted signal power does not depend on the number of subcarrier groups; storoneopredelyayut on the reception OFDM signal subcarriers that impressed interference, if hit at least N1 subcarrier group, the group is considered affected by interference, usually rate allocation for the used subcarrier groups of the next frame, and the need to repeat transmitted to the V velocity data of the current frame is set based on the frequency analysis block error (BLER) of the current and previous frames, use this functional relationship between the probability BLER block error probability and bit error rate BER and upon receipt of each j-th frame, by analyzing the detected parity bit block correctly and incorrectly