ICTACT Journal on Communication Technology

S. S. Rajeshwari ¹, Lajos Hanzo ², Giridhar Krishnamurthy ³

Affiliations
1 Department of Electrical Engineering, Indian Institute of Technology Madras, IN
2 School of Electronics and Computer Science, University of Southampton, IN
3 Department of Electrical Engineering, Indian Institute of Technology Madras, IS

Abstract

In this treatise a two-way Amplify and Forward (AF) relay-aided system is considered, which employs the so-called Arithmetic Sum of Average Bit Error Rate (ASABER) based MIMO precoding technique. The two-way AF relay system is comprised of the pair of transceiver nodes S₁ and S₂, and the Relay Node (RN) R, where each node is equipped with N₁, N₂ and N_r antennas, respectively. We study the effects of varying N_r for fixed values of N₁ and N₂, and as well as the effects of having a fixed transmission power at the RN on the achievable ASABER performance. Based on our intensive simulation campaign, we infer that the attainable diversity order is increased approximately by N_r − min (N₁, N₂), whenever Nr assumes a value higher than min (N₁, N₂) for fixed N₁, N₂ values. However, this is observation is only valid for relay power p_r  (p₁, p₂), where p₁ and p₂ are the transmit power constraints imposed on the sources S₁ and S₂, respectively. We also observe that the ASABER MIMO precoder's BER curve exhibits an error floor for pr ≤ (p₁, p₂).

Keywords

Two-way Relay, Bidirectional Relay, Amplify and Forward, MIMO Precoding.

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