Full-duplex Spatial Modulation Research Articles

Transmit Antenna Selection for Full-Duplex Spatial Modulation Based on Machine Learning

In this paper, we first derive the channel capacity of the full-duplex spatial modulation (FD-SM) system and its upper and lower bounds. Furthermore, different from the traditional optimization-driven decision, we use the data-driven prediction method to solve the transmit antenna selection (TAS) problem in the FD-SM system. Specifically, two novel TAS methods based on the support vector machine (SVM) and deep neural network (DNN) are proposed for reducing the effect of residual self-interference (RSI) on the FD-SM system performance. In our design, we propose a novel feature extraction method based on the principal component analysis (PCA) to help the proposed classifiers improve training. Our simulation results show that our data-driven TAS schemes can approach the optimal performance achieved by exhaustive search while significantly reducing complexity.

Impact of Receiver Non-Idealities on a Full Duplex Spatial Modulation System Performance

In this letter, we analyze, for the first time, the performance of a full-duplex system combined with spatial modulation technique in presence of the receiver non-idealities. IQ imbalance and phase noise are the two radio front-end mismatch factors that have been considered. The impact of the IQ imbalance on the bit error rate (BER) performance of the full-duplex spatial modulation (FDSM) system under different noise levels is investigated. An estimator has also been proposed for the self-interference cancellation (SIC) after the imperfect receiver. The results show that IQ imbalance does not significantly reduce system BER performance at low signal-to-noise ratios. Moreover, it is shown that the proposed estimator is able to maintain the system at an acceptable BER.

On the Performance of Full-Duplex Spatial Modulation MIMO System With and Without Transmit Antenna Selection Under Imperfect Hardware Conditions

Hardware impairments (HI) due to imperfect manufactured electronic parts degrade the performance of wireless systems. In this paper, we consider a bidirectional full-duplex (FD) spatial modulation (SM) multiple-input multiple-output (MIMO) system with non-ideal hardware and residual self-interference (RSI). We propose to use the transmission antenna selection (TAS) as a solution to mitigate this degradation. The performance of the considered system is analyzed using mathematical analysis. Specifically, we first derive the exact closed-form expressions of the outage probability (OP), symbol error probability (SEP), and achievable data rate (ADR) for two cases: with and without TAS. Given these expressions, we conduct a detailed evaluation of the system performance under various scenarios to gain insight into its behavior. Essential conclusions are then made on HI and RSI’s impacts, especially for the case with TAS and high transmission rates.

Closed-Form Expression for the Symbol Error Probability in Full-Duplex Spatial Modulation Relay System and Its Application in Optimal Power Allocation.

Full-duplex (FD) communication and spatial modulation (SM) are two promising techniques to achieve high spectral efficiency. Recent works in the literature have investigated the possibility of combining the FD mode with SM in the relay system to benefit their advantages. In this paper, we analyze the performance of the FD-SM decode-and-forward (DF) relay system and derive the closed-form expression for the symbol error probability (SEP). To tackle the residual self-interference (RSI) due to the FD mode at the relay, we propose a simple yet effective power allocation algorithm to compensate for the RSI impact and improve the system SEP performance. Both numerical and simulation results confirm the accuracy of the derived SEP expression and the efficacy of the proposed optimal power allocation.

Two-Way Full-Duplex Spatial Modulation Systems With Wireless Powered AF Relaying

This letter proposes a dual-hop two-way full-duplex cooperative system, where spatial modulation is used at the sources and energy harvesting is employed at the wireless powered relay. We combine the physical-layer network coding and the fixed-gain amplify-and-forward relaying techniques for two-way transmission. For the simultaneous information and wireless power transfer, the power-splitting protocol is employed at the relay, which has no external power supply. A new unified tight upper-bound bit error rate (BER) expression is derived in a closed-form for both full-duplex and half-duplex transmission schemes. The accuracy of our analyses is verified by various Monte Carlo type computer simulations. The numerical results reveal that the full-duplex scheme can provide considerably better BER performance compared to the conventional half-duplex scheme as the quality of loop-interference cancellation improves and/or the spectral efficiency requirement increases.

A Generalized Transmit and Receive Diversity Condition for Feedback-Assisted MIMO Systems: Theory and Applications in Full-Duplex Spatial Modulation

It is widely exploited that the feedback-assisted multiple-input multiple-output (MIMO) systems, which rely on channel state information (CSI) at the transmitter not only improve the spectral efficiency but also increase the attainable diversity gains. Owing to the limited bandwidth of the feedback channel, it is impractical to feed back perfect CSI or the transmit precoding (TPC) matrix to be used by the transmitter. This issue has been studied for over a decade now and it is addressed by feeding the TPC codeword index back to the transmitter. In this paper, we derive the conditions to be satisfied by the transmit and receive codebooks (TCBs and RCBs) for achieving full transmit and receive diversity gains. Furthermore, based on the conditions derived, we propose several RCBs by exploiting the properties of circulant matrices constructed with the aid of Cyclotomic polynomials. The proposed RCBs are shown to offer several benefits when employed in full-duplex (FD) spatial modulation (SM) systems, which include: 1) reduced hardware complexity of the self-interference (SI) cancellation circuitry, 2) robustness to SI, 3) maintain the diversity gain in the face of strong line-of-sight (LoS) channels. Furthermore, we study the performance of the proposed RCBs in an emerging drone communication scenario where several drones act as FD relays. Our simulation results show that the proposed RCBs indeed do attain the diversity gains predicted by our theoretical results.