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Summary: The proposed research work is on fractal MIMO antenna with microstrip feeding for lower sub‐6 GHz. The design construct's goal is to improve the isolation among the patches and is constructed with a combination of circular strip and rectangular strip slots, and rectangular slots are introduced on the ground plane. The fractal‐shaped MIMO structure composes of FR‐4 material and compact size of 25 × 35 mm2. The current 2 × 1 fractal MIMO radiator resonates at a frequency 3.5 GHz for lower sub‐6‐GHz applications with directional radiation patterns. In this structure, the performance characteristics of design antenna parameters like S‐parameters, surface current distributions, and radiation pattern of the fractal MIMO radiator are investigated. In addition to antenna parameters, MIMO parameters like diversity gain (DG), mean effective gain (MEG), channel capacity loss (CCL), total active reflection coefficient (TARC), and time‐domain analysis parameters are also evaluated. It has been observed that the MIMO parameters of the antenna are in the acceptable range. Fractal‐based prototype MIMO structures are fabricated as well as tested for effective radiation and impedance. The improvised MIMO design that's been installed on a printed circuit board with connector, device housing, compact size, and various types of housing shows better performance compared to the conventionally designed antennas. [ABSTRACT FROM AUTHOR]

Summary: This paper presents a four‐element wideband monopole MIMO antenna. Initially, a single‐element wideband CPW‐fed antenna is designed operating in the range of 4.30 to 6.45 GHz. Using this design, an approach towards MIMO structure is studied. A two‐element structure is designed keeping them adjacent to each other, and the isolation between the antennas is observed. After which, a four‐element structure is designed having the best orientation in order to achieve good isolation between the antenna elements. The proposed antenna configuration has four identical CPW‐fed elements. The proposed configuration has a fractional bandwidth of 40.27% and has a simulated peak gain of 5.5 dBi. This antenna is intended to be used for WLAN, WiMAX, and satellite bands of range corresponding to 4.70–6.19, 5.5–5.7, and 5–6 GHz. All the necessary antenna simulations are simulated using Ansys HFSS and verified on NI AWR Design Environment. The fabricated model of the proposed design is measured for its performance parameters and validated. [ABSTRACT FROM AUTHOR]

In this article, a multiple‐input‐multiple‐output (MIMO) antenna with high isolation is proposed for ultrawideband (UWB) applications. The proposed MIMO antenna consists of two symmetric slot antenna elements with quasi F‐shaped radiators and L‐shaped open‐slots to increase impedance bandwidth. To improve isolation at the lower band, a decoupling network, composed of a narrow slot and a fork‐shaped slot, is introduced in the common ground. The measured results show that the proposed antenna provides high isolation of better than 20 dB over the operating band from 3 to 10.9 GHz. The performances of the UWB MIMO antenna in terms of radiation patterns, peak gain, envelope correlation coefficient, mean effective gain, and diversity gain are also studied. [ABSTRACT FROM AUTHOR]

A patterns diversity slot antenna loaded with a dielectric resonator is presented for on‐body communication systems in 2.45 GHz band. The diversity is achieved by launching even and odd modes on coplanar feed lines resulting in end‐fire and broadside radiation pattern respectively. Loading of dielectric resonator enhances impedance bandwidth and improves isolation between broadside and end‐fire patterns. A common impedance bandwidth of 4% is obtained along with ports isolation of 22 dB. Diversity gain is calculated for three unique on‐body channels and the maximum diversity gain of 8.5 dB is achieved for nonline‐of‐sight on body channel. Large diversity gain and planar geometry makes this antenna suitable for various on‐body communication applications. [ABSTRACT FROM AUTHOR]

Summary: The purpose of this paper is to show how the complementary probability distribution of rain attenuation is drastically changed in the lower rain attenuation range by applying linear combining techniques, namely, equal‐gain combining and the maximal‐ratio combining, discussed in the historical paper by Brennan in 1959. These combing techniques can also be applied to the Automatic Repeat Request techniques. Defined the instantaneous processing gain and the equivalent attenuation in the 3 cases, we show examples of time series of the various parameters, based on the experimental rain attenuation time series recorded with the ITALSAT 18.7 GHz beacon, in a 37.8° slant path in Spino d'Adda (Italy). Then, we report long‐term complementary probability distribution functions of the instantaneous gain and equivalent attenuation, by simulating rain attenuation time series at 19.7 and 39.4 GHz, path elevation angle 35.5°, with the Synthetic Storm Technique, using on‐site measured rain rate time series of 10 years, by simulating the ALPHASAT link at Spino d'Adda. Similar results are also found at different frequencies and elevation angles in Tampa (Advanced Communications Technology Satellite, ACTS result test), the Isle of Guam, and Prague. The main conclusions are as follows: (1) As expected, the instantaneous time diversity gain can be large when the delay time is large and rain attenuation is large; (2) scintillation affects time diversity links as the direct links; (3) equal‐gain and maximal‐ratio combining can add up to 3 dB to the selection diversity gain when the time diversity gain is very small; and (4) equal‐gain and maximal‐ratio combining reduce the fraction of time of rain attenuation in an average year to a value less than the probability of exceeding 3 dB in the link without diversity. [ABSTRACT FROM AUTHOR]

A band notched ultra-wideband (UWB) antenna is presented in this article as a good prospect for multiple-input multiple-output (MIMO)/diversity application. The proposed MIMO antenna is constituted of two modified rectangle-shaped patch antenna elements. A stepped stub is extended from the modified ground plane as a decoupling element between the radiators to realize a good isolation level between them. A band rejection response is obtained by connecting an open resonant stub to each of the radiators. The simulated prototype is fabricated and tested for verification. Results reveal that the proposed prototype provides a 10 dB return loss bandwidth from 3.08 to 10.98 GHz with band notch characteristics from 4.98 to 5.96 GHz, and a good port isolation level ( S21 ≤ 20). Diversity performances are ensured in terms of total active reflection coefficient, envelope correlation coefficient (<0.013 except notch band), diversity gain (≈9.51 dB), mean effective gain ratio (≈1), and channel capacity loss (≤0.35 bps/HZ except notch band). It evidences that the presented band notched UWB antenna can be a good prospective for MIMO/diversity applications. [ABSTRACT FROM AUTHOR]

Since April 2011, ONERA has been operating in Toulouse, France, a beacon receiver able to receive the 20.199 GHz beacon signal of ASTRA 3B. From June 2013 to December 2013, ONERA and CNES successively deployed in the South of France four more beacon receivers in order to characterize the space-time behaviour of the propagation channel at Ka-band. This Site Diversity configuration is of great interest for the development of future high data rate satellite services as it efficiently mitigates severe tropospheric propagation impairments, in particular rain attenuation which is the major issue. The ONERA-CNES Ka-band site diversity experiment consists of three beacon receivers deployed in the area of Toulouse with site separation between 16 and 26 km, and two additional beacon receivers at 140 km and 300 km from Toulouse. This paper aims at providing a complete description of the experimental set-up and the statistical results of the campaign from July 2013 to December 2014. The Complementary Cumulative Distribution Functions (CCDF) of rain attenuation on each site and the Joint Distributions for several pairs of radio links are illustrated. Some comparisons of the measured Diversity Gain with two state-of-the-art prediction models are also presented. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The multiple input multiple output (MIMO) antenna consists of two printed inverted-F antennas whose interelement distance is 7 mm. The isolation of the MIMO antenna is improved since the ground plane is modified to achieve a pattern diversity effect. The measurement results, such as impedance bandwidth, mutual coupling coefficient, radiation pattern were identified as having good performance. The MIMO antenna is further evaluated with an evaluation criterion that includes correlation coefficient and diversity gain, and results indicate successful isolation and diversity performance. All of the results demonstrate that the proposed MIMO antenna is compatible with wireless communication products. [ABSTRACT FROM AUTHOR]

A cylindrical dielectric resonator antenna (CDRA) for multiple-input multiple-output (MIMO) applications is examined in this article. Proposed MIMO radiator achieves high isolation by generating orthogonal modes in CDRA with the help of dual feeding techniques, that is, aperture coupling (port-1) and coplanar waveguide (port-2) techniques. The fractional bandwidth for both port-1 and port-2 is 11.5% (4.9-5.5 GHz). The isolation in operating band between port-1 and port-2 exceed more than 32dB. For validating the optimized simulated results, the archetype of proposed MIMO antenna is fabricated and tested. The diversity performance of proposed structure is also examined and experimentally verified. The proposed radiator is found appropriate for 5.2 GHz WLAN application. [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, a dual band stacked micostrip antenna array is presented for wireless local area network. The antenna is designed and simulated using CST MWSv'14. Stacking of the patches is done to achieve dual band. Further resonant slots are cut on the patch to achieve greater bandwidth. The antenna uses aperture coupled feed with defected ground structure on reduced ground. The antenna is fabricated on FR4 substrate with a dielectric constant of 4.4. The simulated antenna shows a bandwidth of 228.3 MHz from 3.63 to 3.86 GHz and 232 MHz from 5.15 to 5.38 GHz. The simulated gain and envelope correlation coefficient was found to be 6.11 dB and 0.14. The testing of the prototype antenna (to measure S11) is done using vector network analyser. The measured results are matching to the simulated ones. The simulated and the measured results are presented in the article. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:648-654, 2017 [ABSTRACT FROM AUTHOR]

This paper presents the design of space-time block codes (STBCs) over maximum rank distance (MRD) codes, energy-efficient STBCs, STBCs using interleaved-MRD codes, the use of Gaussian integers for STBCs modulation, and Gabidulin's decoding algorithm for decoding STBCs. The design fundamentals of STBCs using MRD codes are firstly put forward for different number of transmit antennas. Extension finite fields (Galois fields) are used to design these linear block codes. Afterward, a comparative study of MRD-based STBCs with corresponding orthogonal and quasi-orthogonal codes is also included in the paper. The simulation results show that rank codes, for any number of transmit antennas, exhibit diversity gain at full rate contrary to orthogonal codes, which give diversity gain at full rate only for two transmit antennas case. Secondly, an energy-efficient MRD-STBC is proposed, which outperforms orthogonal STBC at least for 2 × 1 antenna system. Thirdly, interleaved-MRD codes are used to construct higher-order transmit antenna systems. Using interleaved-MRD codes further reduces the complexity (compared with normal MRD codes) of the decoding algorithm. Fourthly, the use of Gaussian integers is utilized in mapping MRD-based STBCs to complex constellations. Furthermore, it is described how an efficient and computationally less complex Gabidulin's decoding algorithm can be exploited for decoding complex MRD-STBCs. The decoding results have been compared against hard-decision maximum likelihood decoding. Under this decoding scheme, MRD-STBCs have been shown to be potential candidate for higher transmit antenna systems as the decoding complexity of Gabidulin's algorithm is far less, and its performance for decoding MRD-STBCs is somewhat reasonable. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT A dual-port reduced size multiple input multiple output (MIMO) Dielectric Resonator Antenna (DRA) has been studied and proposed. The MIMO antenna consists of a Rectangular Dielectric Resonator antenna, which is fed by two symmetrical feed lines for orthogonal mode excitation. The proposed antenna is suitable for operation over various long term evolution (LTE) bands. A measured bandwidth of 264 MHz for | S11| <−10dB and isolation of 18 dB at 1.8 GHz has been obtained. Besides, the Envelope Correlation Coefficient, Mean Effect Gain and Diversity Gain have been studied for the presented MIMO DRA using the S-parameters. Based on these results, it can be concluded that the proposed antenna can be a suitable candidate for MIMO applications. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:495-501, 2015. [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, an ultrawideband two element multiple-input-multiple-output antenna is presented. The antenna is designed on a low cost FR4 substrate having an overall size of 50 × 90 × 1.52 mm3. The measured −10dB impedance bandwidth covers 1.85-10.6 GHz. The size of each radiator is 12 × 24 mm2 which is 0.011 [ABSTRACT FROM AUTHOR]

In this study, we investigate a new and practical model, ultra-wideband Slepian-Wolf multiple-access relay channel (UWB-SW-MARC) with correlated noises at the relay and receiver, which includes two important models, that is, UWB-SW multiple-access channel with correlated noises and UWB relay channel with correlated noises, as its special cases. We derive a general rate region for UWB-SW-MARC and obtain an outer bound for this model and, thereby, prove two certain capacity theorems for two important and different classes of MARC. Also, we analyze outage probability and diversity gain as the practically important concepts in wireless communications and prove that adding a relay to the multiple-access channel improves the diversity gain. Finally, we evaluate some results numerically and illustrate that the noise correlation coefficient plays an important role in determining the relay position, and show that the channel performance depends on the noise variances. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY A comprehensive analytical framework of a spectrum sharing system, in which secondary receiver (SR) is equipped with multiple antennas, is presented over Rayleigh fading channels. The impact of spatial fading correlation on the performance of spectrum sharing system with maximal-ratio combining at the SR is investigated. In particular, we explicitly derive the CDF and moment generating function of the end-to-end signal-to-noise ratio by assuming a correlation model with arbitrary eigenvalue multiplicities at the SR. On the basis of these results, we conduct an evaluation of secondary system performance in terms of the outage probability, the average symbol error probability, and the ergodic capacity. All analytical results are verified by Monte Carlo simulations. Furthermore, to obtain an insight of system performance, the asymptotic analysis is studied to obtain the diversity gain and the coding gain in the peak transmit power dominated region. Our results show that the diversity gain is unaffected by antenna correlation whereas the coding gain is degraded. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, an improved approach is presented for designing Electromagnetic Bandgap (EBG) reflectors for slot antennas by using a waveguide aperture source in simulating reflection phase test. In this manner the nonplanar nature of the near field at the location of the source, that is, antenna, as well as its loading effect on the reflector are incorporated in the design of a mushroom-type EBG structure operating at 5.3 GHz. This EBG design performs as an efficient reflector in normal wave incidence while suppressing the substrate-bound modes propagating in the azimuthal directions. The designed EBG reflector is employed in several two-slot-antenna structures to establish excellent antenna isolation of at least 25 dB and single antenna gain of 5 dB at 5.3 GHz in each scenario. To further reduce coupling, the antennas are reoriented to benefit from polarization mismatch and radiation pattern nulls, resulting in isolation values of above 40 dB for antennas spaced one wavelength apart. The two-antenna structures are also characterized for MIMO performance in a reverberation chamber and demonstrate an impressive diversity gain of better than 8 dB in a rich multipath environment. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:289-297, 2014. [ABSTRACT FROM AUTHOR]

ABSTRACT Multiple-input multiple-output (MIMO) systems have entailed a great enhancement in wireless communications performances. The use of multiple antennas at each side of the radio link has been included in recent drafts and standards such as WLAN, WIMAX, or DVB-T2. The MIMO performances depend on the antenna array characteristics and thus several aspects have to be taken into account to design MIMO antennas. In the literature, many articles can be found in terms of capacity or antenna design, but in this article, different types of antenna arrays for MIMO systems are measured in a reverberation chamber with and without a phantom as a user′s head. As a result, the MIMO performances are degraded by the user in terms of efficiency, diversity gain, and capacity. Omnidirectional antennas such as monopoles with high radiation efficiency offer the highest performance for a rich scattering nonline of sight indoor environment. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2039-2043, 2013 [ABSTRACT FROM AUTHOR]

Vertical-Bell Labs Layered Space-Time (V-BLAST) system is an emerging spatial multiplexing scheme that can achieve high spectral efficiency. Ordered successive interference cancellation (OSIC) detection algorithm is suitable for V-BLAST system because it can afford a reasonable trade-off between complexity and performance. However, the correlation of a real-world wireless channel may result in a substantial degradation of the OSIC performance. In this paper, the performance of OSIC under correlated fading is analyzed. We obtain the closed-form expression of post-processing signal-to-noise ratio (SNR) for each sub-stream based on V-BLAST architecture, and then derive the distribution of post-processing SNR based on multivariate statistical theory. The upper bound of the average probability of error (APE) is derived by the nearest neighbor union bound theory. From the expression of APE for each sub-stream, it is shown that the diversity gain at the ith processing step is ( N − M + i), where N and M are the number of receive and transmit antennas, respectively. Correlation can decrease the effective post-processing SNR rather than the diversity gain, and the decreased amount of the effective post-processing SNR is accurately measured by the corresponding diagonal element of the inverse of the transmit correlation matrix. The optimal ordering can improve the performance and this advantage vanishes gradually as the scattering angle decreases. Copyright © 2010 John Wiley & Sons, Ltd. In this paper, the performance of OSIC under correlated fading is analyzed. Correlation can decrease the effective post-processing signal-to-noise ratio (SNR) rather than the diversity gain, and the decreased amount of the effective post-processing SNR is accurately measured by the corresponding diagonal element of the inverse of the transmit correlation matrix. The optimal ordering can improve the performance and this advantage vanishes gradually as the scattering angle decreases. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The diversity performances of the wireless devices operating in a multipath propagation environment are usually presented in terms of correlation coefficient, diversity gain and effective diversity gain. These parameters can be measured in reverberation chamber. This paper presents some active measurements of antenna diversity performances on a small wireless terminal in several realistic environments. The measurements were performed in the WiMax band, i.e. at 3.5 GHz, in a reverberation chamber where the channel is statistically uniform, in a real indoor propagation channel, and in an outdoor-to-indoor environment. The diversity performances are evaluated by using a specific test-bed constituted by an arbitrary signal generator and two radio-frequency digitizers. The effectiveness of diversity is presented in terms of effective diversity gain, signal to noise ratio, bit error rate and frame error rate. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010. [ABSTRACT FROM AUTHOR]

In the cellular systems diversity reception techniques such as space, time, frequency, polarization, and pattern diversity are widely used to minimize or mitigate the effect of multipath fading due to scattering, diffraction, and reflection of the transmitted signal. Practically, these methods can be applied either at the base station or at the mobile terminal. In the on-body environment, fading has also been found to be significance. Space diversity has been useful in such channels. In this article, a switching parasitic disk-loaded monopole array antenna (also called pattern diversity antenna) was used to investigate diversity performance in on-body channels. There were five body channels that have been investigated that are belt-to-chest, belt-to-wrist, belt-to-ankle, belt-to-head, and belt-to-back channels. The diversity data was analyzed using a switched diversity combining method. Diversity gain has been measured at outage of 1% and 10% for five on-body channels. The results show significance gains are achieved for nonline-of-sight channels especially the ankle and wrist channels which have involved lots of antenna movement. In contrast, very little gain is obtained for line-of-sight channel particularly for the chest channel as only one beam was used for most of the time. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1157–1161, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24274 [ABSTRACT FROM AUTHOR]

A novel wideband printed diversity antenna for mobile handsets is proposed and studied. The antenna consists of two monopoles with symmetric configuration. The effects of some parameters of the proposed antenna are studied. The measured relative bandwidth reaches to 29.0% (1860–2490 MHz) with acceptable isolation over the bandwidth. The measured radiation patterns of the two monopoles cover complementary space regions. The diversity performance is approximately calculated, and the results show that the proposed antenna can provide spatial and pattern diversity. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 218–222, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23948 [ABSTRACT FROM AUTHOR]

This article presents an experimental investigation on the diversity performance of a reconfigurable antenna integrating a SPDT for polarization switching. The antenna is characterized in terms of its envelope correlation factor, mean effective gain, and diversity gain (DG) in a multipath indoor environment. The influence of the antenna placement and orientation is emphasized. Low correlation factors and large DGs are observed making this device highly performing for indoor wireless communication systems. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 3154–3158, 2007; Published online in Wiley Inter-Science (www.interscience.wiley.com). DOI 10.1002/mop.22904 [ABSTRACT FROM AUTHOR]

This study investigates the performance of planar fixed and/or pattern reconfigurable antennas on a model laptop in terms of diversity gain and spatial coverage. The reconfigurable antenna used in this work has the ability to change its radiation pattern from endfire to broadside while operating over a common impedance bandwidth. The research combines diversity gain and spatial coverage into a single parameter that takes into account the effects of both simultaneously. Experimental data, including the resulting diversity gain and spatial coverage calculations, are presented. This work reveals the possibilities and importance of using reconfigurable radiation antennas and weighs their potential impact on high performance wireless systems. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 535–539, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22181 [ABSTRACT FROM AUTHOR]

The embedded element patterns of two parallel half-wavelength dipoles are calculated for various source impedances and dipole spacings by using classical formulas for self and mutual impedances. These are used to calculate the effective diversity gain, which is shown to vary with source impedances and dipole spacing. The results are verified using a method of moments (MoM) code for wire antennas and via measurements in a reverberation chamber. The numerical model is used to find the source impedances that maximize the effective diversity gain, which has a maximum for the computed cases when the source impedances are conjugate-matched to the input impedances of each of the embedded dipole elements. Then the two antenna ports are uncorrelated. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 532–535, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21400 [ABSTRACT FROM AUTHOR]

The performance of a multiple‐input multiple‐output amplify‐and‐forward two‐way relay network with joint antenna and relay selection is analysed over Nakagami‐m fading channels. Both approximate and asymptotic system outage probability expressions are derived, and diversity and coding gains for an arbitrary number of antennas, relays and fading severity are presented. Finally, the analytical findings are verified by numerical examples. [ABSTRACT FROM AUTHOR]

In a wireless communication system, the performance of the system is degraded due to the attenuation of the signal by path loss when a user is distant from the base station. For improvement of the system in this case, a new scheme is proposed. In conventional schemes, the source can transmit to the destination belonging to own cell coverage. In the proposed scheme, the destination can receive the additional signal from another base station through multiple relays. Therefore, the proposed scheme provides higher diversity gain and better performance than the conventional scheme. [ABSTRACT FROM AUTHOR]

Considering the most general case that each node transmits with unequal powers, an efficient relay selection scheme is proposed for the two‐way amplify‐and‐forward (AF) relaying system, which bypasses the need for channel estimation and can be implemented by comparing the product of each relay's local transmit power and its received pilot signalling powers from the two sources. A tight closed‐form lower bound for the system outage probability is derived in Nakagami‐m fading, followed by the analysis of diversity and coding gains. Simulation results are presented to corroborate analysis. [ABSTRACT FROM AUTHOR]

An asymmetric multi‐way relay communication scheme using orthogonal projection and analogue network coding is proposed. The scheme is designed for the wireless sensor network, where one sink node (SN) exchanges information with multiple user nodes via a relay station and both the SN and user nodes have low complexity structures. It has been observed that the minimal number of the relay antennas can be smaller than that of the total data streams. Moreover, when the number of the relay antennas is larger than the minimum, a paired throughput based max–min criterion with low computational complexity is developed to select the optimal relay antenna subset and guarantee full diversity gain. The numerical results demonstrate the high performance of the proposed communication scheme and antenna subset selection criterion. [ABSTRACT FROM AUTHOR]

Summary: The Alamouti space‐time block code (STBC) achieves full diversity gain at a rate of 1/2. However, the Alamouti scheme does not provide multiplexing gain. The Silver code offers both diversity and multiplexing gain. It has a minimum normalization determinant of 1/7. The Golden code is another STBC that offers both diversity and multiplexing gain. The Golden code is ranked higher than the Silver code because of its lower minimum normalization determinant of 1/5, however, the golden code suffers from a high detection complexity in the modulation order of M4. The 3/4‐Sezginer code is another STBC, which compromises between the Alamouti scheme and the Golden code in terms of diversity gain and multiplexing gain. The 3/4‐Sezginer code achieves full diversity and half of multiplexing gain. The uncoded space‐time labeling diversity (USTLD) is a recent scheme that improves the error performance when applied to the STBC in multiple‐input multiple‐output (MIMO) systems and will be applied to the 3/4‐Sezginer STBC to improve the error performance in this paper. The theoretical error probability for both the 3/4‐Sezginer STBC and the improved system is formulated using the union bound in this paper. The theoretical error probabilities of both 16‐QAM and 64‐QAM are validated through Monte Carlo simulation. The simulation and theoretical results show that the proposed system with 4 NR can achieve an SNR gain of 1 dB for 16‐QAM and 1.2 dB 64‐QAM at a bit error rate (BER) of 10−6. [ABSTRACT FROM AUTHOR]

Summary: The Golden code has full rate and full diversity. The Golden codeword matrix contains two pairs of super symbols. Based on one pair of super symbols, two modulation schemes, Golden codeword–based M‐ary quadrature amplitude modulation (GC‐MQAM) and component‐interleaved GC‐MQAM (CI‐GC‐MQAM), are proposed for single‐input multiple‐output (SIMO) systems. Since the complexities of the maximum likelihood detection for the proposed GC‐MQAM and CI‐GC‐MQAM are proportional to O(M2) and O(M4), respectively, low complexity detection schemes for the proposed GC‐MQAM and CI‐GC‐MQAM are further proposed. In addition, the theoretical average bit error probabilities (ABEPs) for the proposed GC‐MQAM and CI‐GC‐MQAM are derived. The derived ABEPs are validated through Monte Carlo simulations. Simulation and theoretical results show that the proposed GC‐MQAM can achieve the error performance of signal space diversity. Simulation and theoretical results further show that the proposed CI‐GC‐16QAM, ‐64QAM, and ‐256QAM with three receive antennas can achieve approximately 2.2, 2.0, and 2.1 dB gain at a bit error rate of 4 × 10−6 compared with GC‐16QAM, ‐64QAM, and ‐256QAM, respectively. [ABSTRACT FROM AUTHOR]