A Constellation Scaling Approach to Vector Perturbation for Adaptive Modulation in MU-MIMO

Abstract

Abstract-It is known that vector perturbation (VP) precoding does not apply to the case where users employ different modulations, while existing solutions for this scenario are suboptimal. In this letter, a joint vector perturbation precoding algorithm is proposed for multiuser MIMO (MU-MIMO) downlink system in the adaptive modulation scenario where different users apply different modulation types. Compared with conventional block diagonalized vector perturbation (BD-VP) and user grouping VP where the search dimension of the perturbation vector is reduced, the proposed algorithm keeps the search dimension unchanged by applying a simple transformation to the VP operation. Our analysis and results show that the proposed algorithm provides an applicable VP solution to the adaptive modulation scenario, with optimal VP performance.

A Tutorial on Interference Exploitation via Symbol-Level Precoding: Overview, State-of-the-Art and Future Directions

“…An additional problem for conventional VP precoding in [107] is that it does not apply to multi-modulation scenarios, since the perturbation basis is modulation dependent [107]. To overcome this, several studies have considered multi-modulation VP precoding, which includes the block-diagonalized VP method in [111], the user-grouping VP method in [112], and the constellation scaling approach in [113], [114].…”

On the Achievable Performance-Complexity Tradeoffs of Relay-Aided Space Shift Keying

“…where R av is the average rate, C is the complexity of the demodulation scheme used (as given in Table I), and P C in mW/Mflops denotes the power consumption per 10 6 flops of the digital signal processor (DSP) [65]. P cd = P syn + P LNA + P mix + P IFA + P filr + P ADC is the power consumption of the circuit blocks at the destination, where, P syn , P LNA , P mix , P IFA , P filr , and P ADC are the power consumption values for the frequency synthesizer, the Low-Noise Amplifier (LNA), the mixer, the Intermediate Frequency Amplifier (IFA), the filters, and the analog-to-digital converter, respectively.…”

Tunable load MIMO with quantized loads

“…The dirty paper coding (DPC) proposed in [1] can achieve the channel capacity by subtracting the interference before transmission, which is however difficult to implement in practice due to the complexity and the assumption of infinite codeword length. Non-linear precoding schemes such as Tomlinson-Harashima precoding (THP) [2] and vector perturbation (VP) precoding [3] [4] are then proposed and can approach the performance of DPC. On the other hand, linear precoding schemes that require much less computational complexity have received increasing research attention.…”