Application And Research Of Polar Codes In WLAN

As we all know,wireless local area network(WLAN)is an indispensable part in scientific research,daily work and even daily life.Since WLAN is so important,it is of practical significance for us to study the application of new channel coding scheme.The WLAN channel is a fading channel,and IEEE802.11 standards organization also developed a series of standards for WLAN.In 2009,E.Arikan proposed the polarization phenomenon of the channel,and then proposed the polar codes.Until now,polar codes are still a relatively new channel coding scheme.Its most significant advantage over other mainstream coding is that it can theoretically reach the Shannon limit.In addition,the coding and decoding of polar codes is relatively easy,and it is undoubtedly advantageous in practical application.The work of this thesis is to study the application of polar codes in WLAN.The main contents are as follows:1)The wireless channel model is determined.Unlike the most common AWGN,WLAN channel is a kind of fading channel.Point-to-point wireless communication model is the focus of this thesis,established as Rayleigh fading channel model.The polarization codes of CSI and CDI are discussed in detail.2)An improved Monte Carlo polarization code construction method is proposed.The polar codes are different from other channel codes in that its coding is based on the channel model.The construction of the polar codes is usually constructed by Monte Carlo construction method.Based on the original Monte Carlo construction method,An improved algorithm is proposed in this thesis,which improves the original algorithm by recalculating the transfer probability of the output partition.3)A polar codes construction method based on degraded channel and upgraded channel is proposed.This method is proposed by Ido Tal in its literature,but it is only applied to AWGN channel.The feasibility of the scheme for Rayleigh fading channel is discussed and realized by simulation.4)The performance is analyzed by simulation results.SC-CRC and SCL-CRC is adopted in decoding scheme..After comparing the two new polars code construction schemes,the performance of LDPC codes mentioned in the standard is compared.The length of the polarized code is ?.We compare the performance of the polar codes with 512,1024 and 2048 and the LDPC codes with 648,1296 and1944.It is concluded that the performance of the improved Monte Carlo polar codes construction method is little different from that of the original method.Compared with the polar codes constructed by Monte Carlo,the polar codes based on degraded channel and upgraded channel have better performance in a certain signal-to-noise ratio.Compared with LDPC codes,the performance of polar codes is better when the code length is shorter than that of LDPC codes,and the performance of polar codes is better when the code length is longer.