Differential Spatial Modulation Research Articles

Corrections to “Bandwidth-Efficient Generalized Differential Spatial Modulation”

Corrections to “Bandwidth-Efficient Generalized Differential Spatial Modulation”

An Enhanced System Model for Differential Spatial Modulation System Under Fast Fading Channels and a Corresponding DFDD Based Low- Complexity Detector

An Enhanced System Model for Differential Spatial Modulation System Under Fast Fading Channels and a Corresponding DFDD Based Low- Complexity Detector

Low-Complexity Detectors for Space-Time Block Coded Differential Spatial Modulation

Low-Complexity Detectors for Space-Time Block Coded Differential Spatial Modulation

Differential Spatial Modulation with Lattice Reduction Aided Pre-coding

This paper presents a pre-coding scheme for recently proposed differential spatial modulation (DSM) systems. It employs a lattice reduction (LR) aided pre-coding approach. An approximated upper bound on average bit error rate (BER) is semi-analytically derived. It is analytically shown that it can achieve a full diversity gain. That is, the performance analysis demonstrates that the LR-aided pre-coding DSM (LR-PDSM) systems with transmit antennas and receive antennas can achieve the maximum transmit diversity order of . Meanwhile, it is well-known that the diversity order attained by the conventional zero-forcing (ZF) pre-coding is given as . Simulation results verify the approximated theoretical analysis and show that LR-aided ZF pre-coding is capable of improving the BER performance of the conventional ZF pre-coding based DSM systems under the same spectral efficiency.

Genetic Algorithm Aided Compressed Sensing Detector for Differential Space-Time Media-Based Modulation

Differential spatial modulation (DSM) is a multi-antenna technique that does not require channel state information (CSI). However, DSM has a deficiency of low spectral efficiency (SE). In this paper, a differential space-time media-based modulation (DSTMBM) system is proposed. The DSTMBM system equips radio frequency (RF) mirrors to transmit additional bits, which leads to an improvement of SE. Simulation results show that the bit error rate (BER) performance of DSTMBM is about 4dB better than that of DSM under the same parameters. For low-complexity implementation, a genetic algorithm aided compressed sensing (GA-CS) detector is tailored to the DSTMBM system. Compared with the state-of-the-art low-complexity detector with the best performance in differential systems, the GA-CS detector achieves a complexity reduction of 3 orders of magnitude when the transmit matrix dimension is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$8\times 8$</tex-math></inline-formula> , at the cost of only around 1dB in terms of BER performance. Furthermore, the complexity of GA-CS detector does not grow exponentially with the matrix dimension.

Generalized Distributed Multiple Turbo Coded Cooperative Differential Spatial Modulation

Generalized Distributed Multiple Turbo Coded Cooperative Differential Spatial Modulation

Polar Coded Cooperative Differential Spatial Modulation Based on Plotkin Construction and Quasi-Uniform Puncturing

Coded-cooperation combines virtual MIMO transmission and channel coding to achieve forward error correction while achieving diversity gain. It is a promising technology in 5G communications. The polar code is the only channel coding technology that can theoretically achieve Shannon limit transmission, which make it the preferred coding technology in cooperative communication. In this paper, we proposed a new wireless communication scheme, which is a polar coded cooperative spatial modulation schemes based on Plotkin construction and Quasi-uniform puncturing (QUP). First, we adopt Plotkin construction based on the inverted codeword of the polar code to get a cooperation method, which offer a significant improvement in performance on the polar code cooperation under fading channels. We analyze the decoding characteristics of the inverted codewords and then introduces the QUP method to improve the cooperation benefits. At the same time, we extend the cooperation scheme with differential spatial modulation for the proposed coded cooperative schemes. The new coded-cooperation scheme outperforms its coded non-cooperative counterpart schemes under identical conditions, as expected. Monte Carlo simulated results show that the proposed cooperative schemes outperform their corresponding non-cooperative counterpart schemes, by the gain of 2.5 dB with 1024 code length and 0.25 code rate under identical conditions.

Long-Block Differential Spatial Modulation

Spatial modulation (SM) can transmit additional data bits by selecting antennas and avoids synchronization and interferences among antennas. Differential SM (DSM) is a noncoherent technique of SM, but it is less bandwidth efficient than SM. This paper proposes a novel DSM scheme called long-block DSM (LB-DSM), whose block is longer than the original DSM’s. Each block of LB-DSM consists of two parts. One part is the block of the original DSM, and the other is similar to SM. With the aid of the latter part, the data rate of LB-DSM is higher than that of DSM. Besides, we propose bit mapping and low-complexity noncoherent maximum-likelihood detection for LB-DSM, by which LB-DSM is less complicated than DSM. In addition to higher bandwidth efficiency and lower decoding complexity, distance analysis and computer simulation results indicate that LB-DSM provides better error performance than DSM for 8PSK (eight-ary phase shift keying). Furthermore, the idea of LB-DSM is applied to generalized DSM (GDSM), which activates more than one transmit antenna each time. The resulting scheme, called long-block GDSM, offers better bandwidth efficiency and error performance than GDSM.

Bandwidth-Efficient Generalized Differential Spatial Modulation

Differential spatial modulation (DSM) can transmit additional data bits by selecting indexes of antennas without the pilot overhead and increasing radio frequency circuits and power consumption. DSM is extended to generalized DSM (GDSM) where more than one transmit antennas are activated each time. However, the transmission rate of the existing GDSM scheme is low. In this paper, we propose a new GDSM scheme that uses symbol interleaving on differential space-time modulation. The number of interleaving patterns is derived, and interleaving patterns with transmit diversity two are created as well. By selecting the interleaving patterns, the proposed scheme has higher data rates than the existing GDSM scheme. We also propose low-complexity detectors for both schemes. Theoretical analysis and computer simulation both show that the proposed scheme has satisfactory error performance.

Evolutionary gravitational Neocognitron neural network based differential spatial modulation detection scheme for uplink multiple user huge MIMO systems

Interfering manipulation is a growing number of bright aspects for 6th generation (6G) infrastructure, particularly to detect huge sequence quadrature amplitude modulation (QAM) signals. In this manuscript, an evolutionary gravitational Neocognitron neural network based differential spatial modulation detection scheme (EGNNN-DSMDS) is proposed for uplink multiple user huge multiple input multiple output (MIMO) systems. To prevent the wastage of antenna resources, massive MIMO uplink systems use the differential spatial modulation (DSM), here the transmitter is equipped with a small count of antennas, whereas the receiver is equipped with a huge count of antennas. By utilizing the asymptotic characteristics of massive multiple input multiple output channels, the transmitting signal can be uniquely decoded without instantaneous channel state information in the receiver. When analyzed with conventional coherent zero-forcing detector (ZFD), the proposed approach has less complication. The proposed EGNNN-DSMDS detection scheme achieves excellent bit error ratio performance and estimating channel errors. EGNNN-DSM attains higher spectral efficiency 99.56%, 96.33%, 98.11%, lower BER 2.5%, 4.13%, 1.19% and lower computational complexity 1.19%, 2.16%, 1.15% compared with existing methods, like MLPNN-MUD-UMM-MIMO, CNN-LASD-UMM-MIMO, and DNN-SRD-UMM-MIMO. Finally, the proposed EGNNN-DSM detection scheme attains the better outcomes.

Reordered Amplitude Phase Shift Keying Aided Differential Spatial Modulation: DFDD-Based Low-Complexity Detector and Performance Analysis Over Fading Channels

Differential spatial modulation (DSM) is a multiple input multiple output (MIMO) wireless transmission technique that achieves additional data bit transmission by utilizing antenna activation indexes. Combined with amplitude phase shift keying (APSK) constellations, the spectrum efficiency of DSM system can be further improved. However, the theoretically optimal maximum likelihood (ML) detection suffers from a high complexity that grows exponentially with the number of transmit antennas (TAs). Besides, the imperfect channel state information in fast fading channels leads to a severe deterioration of the detection performance. To address these problems, we propose a novel transmission scheme named reordered amplitude phase shift keying aided differential spatial modulation (RAPSK-DSM) and its low-complexity decision-feedback differential detection (DFDD) based detection algorithm. The proposed RAPSK-DSM scheme provides a better solution for addressing the error propagation problem and its detector utilizes the preceding channel gain vectors from previous detection results to mitigate the performance loss caused by time-selective channel fading. Furthermore, by decomposing and pre-computing the detection process, the complexity of proposed detector is effectively reduced due to the avoidance of redundant computations. Numerical analyses and simulation results show that the proposed RAPSK-DSM system is able to achieve substantial bit error rate (BER) performance improvement under fast fading channel conditions at the expense of low complexity.

A Low-Complexity Soft-Output Detector for Differential Spatial Modulation

Differential spatial modulation (DSM) can avoid pilot overhead and transmit additional data bits without increasing the number of radio frequency chains. If DSM is concatenated with a channel code, which can improve DSM’s error performance, the detector’s output for DSM ought to be soft-decision. The complexity of the MAP (maximum <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">a posteriori</i> ) and Max-Log-MAP detectors increases exponentially with the number of transmit antennas, and the only existing reduced-complexity soft-output detector for DSM is derived from the Max-Log-MAP detector. In this letter, we propose a new low-complexity soft-output detector, which simplifies the MAP detector. The complexity of the proposed detector increases only linearly with the number of transmit antennas. Simulation results show that the error performance of the proposed detector is close to that of the MAP detector. Besides, the proposed detector outperforms the Max-Log-MAP detector and the existing detector with respect to both complexity and error performances.

Differential space time media‐based modulation system

Differential spatial modulation (DSM) is a multi-antenna differential technology with low power consumption and no demand of channel estimation. It is suitable for communication systems that have fast migration velocity and high requirements for both power consumption and complexity. However, due to the sparse structure and the requirements of differential coding, the spectral efficiency is limited. Therefore, media-based modulation (MBM) technology is introduced into differential system in this work to improve the spectral. A differential space time media-based modulation (DSTMBM) system is proposed. While retaining the inherent advantages of the DSM, the additional bits are transmitted through the radio frequency (RF) mirrors in DSTMBM. Unlike traditional DSM, the transmit antenna of DSTMBM system can be activated multiple times. In addition, a theoretical performance is derived, and a low-complexity (LC) detection algorithm is adopted. Simulation results show that the DSTMBM system has a performance advantage of about 4.5 dB at a high transmission rate compared to traditional DSM systems. Monte Carlo simulation matches the theoretical performance in a wide range. Meanwhile, the LC detection algorithm reduces the complexity by 2–3 orders of magnitude without the bit error rate (BER) performance loss.

A DFDD Based Detector for Space-Time Block Coded Differential Spatial Modulation Under Time-Selective Channels

Space-time block coded differential spatial modulation (STBC-DSM) is a recently proposed spectral efficient multiple-input-multiple-output (MIMO) transmission technique. Existing detection algorithms for STBC-DSM are designed for quasi-static channels, which limits the application of STBC-DSM in fast fading channels. In this letter, we propose a novel decision-feedback differential detection (DFDD) based detector for STBC-DSM system under fast-fading channels. The proposed detector mitigates the impact of channel vector changes by using the DFDD metric which contains multiple previous detection results. Simulation results show that the proposed detector is more tolerable in time-selective channels than other existing STBC-DSM detectors.

High Dimensional Differential Optical Spatial Modulation with High Spectrum Efficiency

High Dimensional Differential Optical Spatial Modulation with High Spectrum Efficiency

Performance analysis of precoding‐aided differential spatial modulation systems with transmit antenna selection

In this paper, the performance of precoding-aided differential spatial modulation (PDSM) systems with optimal transmit antenna subset (TAS) selection is examined analytically. The average bit error rate (ABER) performance of the optimal TAS selection-based PDSM systems using a zero-forcing (ZF) precoder is evaluated using theoretical upper bound and Monte Carlo simulations. Simulation results validate the analysis and demonstrate a performance penalty < 2.6 dB compared with precoding-aided spatial modulation (PSM) with optimal TAS selection. The performance analysis reveals a transmit diversity gain of for the ZF-based PDSM (ZF-PDSM) systems that employ TAS selection with transmit antennas, selected transmit antennas, and receive antennas. It is also shown that reducing the number of activated transmit antennas via optimal TAS selection in the ZF-PDSM systems degrades ABER performance. In addition, the impacts of channel estimation errors on the performance of the ZF-PDSM system with TAS selection are evaluated, and the performance of this system is compared with that of ZF-based PSM with TAS selection.

Differential STBC-SM Scheme for Uplink Multi-User Massive MIMO Communications: System Design and Performance Analysis

In this paper, a novel differential space-time block coded spatial modulation (differential STBC-SM) is proposed for uplink multi-user massive multiple-input multiple-output (MIMO) communications, which combines the concept of differential coding and STBC-SM to enhance the diversity benefits in the absence of the channel state information (CSI). The transmission structure of the proposed system is on a block basis, where each block contains two sub-blocks. More specifically, the first sub-block only conveys amplitude and phase modulation (APM) symbol bits, since its transmit antennas (TAs) obey a pre-designed activation pattern, which do not carry any information bit. For the second sub-block, the input bits are modulated to STBC-SM matrices, which are then differentially coded between two adjacent sub-blocks. Moreover, a novel block-by-block based non-coherent detector is presented. Finally, we derive an upper bound on the average bit error probability (ABEP) by using the moment generating function (MGF). Our simulation results show that the proposed differential STBC-SM transmission structure is able to acquire considerable bit error rate (BER) performance improvements compared to both the conventional differential spatial modulation (DSM) and differential Alamouti schemes.

A Differential Modulation Scheme for Metasurface-Based Terahertz Communications

Metasurface-based terahertz (THz) modulators, which carry information by changing the spatial pattern of the metasurface at every symbol time, are an important component to establish low-cost low-energy–consuming THz communication systems. This paper proposes a differential spatial THz modulation (DSTM) scheme for metasurface-assisted THz communications. In DSTM, the metasurface pattern activation orders are employed to carry information, instead of the metasurface patterns themselves. In this way, the DSTM receiver can perform differential detection without knowing the metasurface response to incident THz signals and the channel state information. The proposed DSTM scheme is applicable to all kinds of metasurfaces enabling THz communications, including transmissive metasurfaces and reflective metasurfaces. For high-rate DSTM systems, we propose an efficient bits-to-activation-order mapping method and a low-complexity detection method. Simulations are conducted to demonstrate the performance of the proposed scheme. It is shown that the proposed scheme pays acceptable penalty compared to the non-differential modulation scheme with coherent detection, which needs to know the metasurface response to the incident signals as well as all the channel state information.

Adaptive secure transmission for wireless powered communication networks

This paper investigates secure transmission in a wireless powered communication network (WPCN) with an energy harvesting (EH) source configured with multiple antennas. In the WPCN, the EH source harvests energy from the radio frequency (RF) signals broadcasted by a power beacon (PB), and purely relies on the harvested energy to communicate with the destination in the presence of passive eavesdroppers. It is noteworthy that the RF-EH source is equipped with a finite energy storage to accumulate the harvested energy for the future usage. Moreover, due to energy-constraint and complexity- limitation, the multi-antenna source is only configured with a single RF-chain. To enhance the security for the WPCN, we propose two adaptive transmission schemes, i.e., energy-aware transmit antenna selection (EATAS) and energy-aware differential spatial modulation (EADSM). According to the energy status and the channel quality, the source adaptively decides whether to transmit confidential information or harvest RF energy. To evaluate the secrecy performance of the proposed schemes, we first study the evolution of the energy storage, and then derive the analytical expressions of connection outage probability (COP), secrecy outage probability (SOP) and efficient secrecy throughput (EST). Numerical results demonstrate that our proposed schemes outperform the existing schemes, i.e., time-switching based TAS (TS-TAS) and accumulate-then-transmit (ATT). And, increasing the transmit power of the PB or the capacity of the source's energy storage is helpful to improve the secrecy performance. Moreover, there exists an optimal transmission rate for each proposed scheme to achieve best secrecy performance.

Improved Schemes of Differential Spatial Modulation

Differential spatial modulation (DSM) is able to transmit additional data bits without increasing the number of radio-frequency chains and power consumption and also avoids pilot overhead. In this paper, we propose two new schemes of DSM to improve the original DSM. One is an increased-rate scheme that transmits one additional data bit per two blocks. The bit mapping and maximum-likelihood detection is particularly designed. The goal of the second scheme is to increase the diversity of DSM. By properly designing block coded modulation and complex antenna-index matrices, the proposed scheme can achieve the desired diversity order. Compared with the existing schemes with the same constellation of the transmitted signals, the proposed scheme achieves higher transmission rates.