Research And Realization Of Channel Coding And Channel Estimation Face To C-RAN

The competitiveness of conventional wireless access network in mobile internet havebeen seriously weakened because of the fierce competition in the market. It is proposedthat cooperative wireless network composed of remote wireless radio frequency units andantennas based on centralized baseband pool as well as the Cloud Radio Access Network(C-RAN), a wireless access network which is based on open platform and real-time cloudstructure. Under this background, researches on channel coding and channel estimation indata channel baseband processing have been carried out in this paper.According to the requirements of C-RAN write paper, multi-mode high speedchannel encoder is designed in channel coding. This encoder uses8bit high speedprocessing scheme which can support Recursive Systematic Convolutional Code (CRC)encode, interleave and channel encode in Global System for Mobile communication(GSM)/Time Division-Synchronous Code Division Multiple Access (TD-SCDMA)/LongTerm Evolution (LTE). By Field Programmable Gate Array (FPGA) verification, thisscheme is better than traditional scheme on resource consumption and computing time.In the regard of channel estimation, combining C-RAN, Long Term EvolutionHotspot/indoor (LTE-Hi), Block Repeat Orthogonal Frequency Division Multiple Access(BR-OFDMA) and compressed sensing technology, an algorithm to generate pseudorandom pilot pattern is put forward and a new pilot pattern had been also designed. Thispilot pattern shows superiority in solving the problem of traditional compression sensingchannel estimation which is not conducive to real-world applications.it is not only meetthe randomness of pilot pattern, but also make the sending and receiving sides obtain thepilot position. Simulation results show that the performance of the scheme is more ideal,and better than traditional scheme under the edge interference situation.In the aspect of channel estimation, an adaptive block weighted matching pursuitalgorithm is designed. According to the channel characteristics of LTE-Hi, this algorithmcan conduct compression sensing channel estimation without the knowledge of thechannel sparsity and SNR. Scheme combined with channel estimation and channeldecoding is adopted in this paper, which conducted iterative estimation and decoding.Simulation results show that this scheme is better than traditional scheme in channelestimation accuracy, the error rate and computation time. Finally, the hardware platform was introduced in this paper, on which the algorithmsabove were implemented. The test results of the hardware showed the the sheme could berealized and the performance could meet the requirements of C-RAN.