A RPC Decoding Algorithm Based On Matrix-Split

Random projection code is a blind seamless rate adaptation technology. It has the following advantages: the sender need not know the channel state information; transmission rate adaptation is somooth; high spectral efficiency can be achieved. However, the RPC decoding process requires a lot of convolution, so that its computational complexity is very high. Therefore, it's difficult to design and implement a high speed RPC decoder and this problem restrict RPC's application in high-speed wireless communication system. To tackle this problem, this paper propose a low complexity RPC decoding algorithm. The complexity of the proposed algorithm is lower than traditional method, while preserving the same performance.At first, we introduce the principle of RPC encoding and decoding, and analyze the factors that influence RPC decoding algorithm complexity. The analysis revealed that the major computation existed at constraint nodes and depend on the weight set. Based on the analysis, this paper proposes a low-complexity RPC decoding algorithm. The basic idea is to split the RPC encoding matrix so that we can regard RPC symbol as the superposition of several symbols. The decoder decode these symbols respectively to obtain a lower complexity. Simulation results show that the proposed low complexity RPC decoding algorithm's computational complexity can be ruduced to 44% of traditional algorithm, while two algorithm preserving the same performance. This proposed algorithm also can be used for multiple access communication system. Analysis showed that in the multi-access scenario, the amount of calculation required by low complexity RPC decoding algorithm can be ruduced to 5% of that required by traditional algorithm. And the simulation results indicate both algorithm have the same performance.The proposed low complexity RPC decoding algorithm can perform as well as traditional algorithm with a lower computational complexity. A higher speed RPC decoder can be designed by using this proposed algorithm. And it's benefitial to the appliacation of RPC in high-speed wireless communication system.