Energy efficiency based concatenated LDPC and turbo codes for wireless sensor networks

Abstract

Recently wireless sensor networks have been shown to be very attractive for many wireless communications applications. A large number of very tiny sensors spread over the area under consideration constitute the wireless sensor networks. These tiny sensors have limited power resources. Due to limited built-in battery life-time at each sensor, minimizing power consumption in the sensors is an important issue for reliable and sustainable network operation. Error control coding (ECC), such as turbo codes and Low Density Parity Check (LDPC), is a classic approach used to increase link reliability and lower the required transmitted power. However, lowered power at the transmitter comes at the cost of extra power consumption due to the decoder at the receiver. Stronger codes provide better performance with lower power requirements, but have more complex decoders with higher power consumption than simpler error control codes. Turbo codes shows good performance at low SNR with iterative decoding but error floor phenomenon is occurred at high SNR region. LDPC code shows good performance at high SNR without error floor in contrast to turbo code. Therefore, LDPC code can be concatenated to turbo code to reduce error floor. In this paper, an energy efficiency based serially concatenated scheme of Low Density Parity Check (LDPC) and turbo codes scheme is proposed. The proposed scheme is discussed, analyzed, and evaluated. The performance of the proposed scheme is investigated through computer simulations, which shows an improvement in the bit error rate (BER).