Classic Shannon theory suggests that the achievable channel capacity increases logarithmically with the transmit power. By contrast, the MIMO capacity increases linearly with the number of transmit antennas, provided that the number of receive antennas is equal to the number of transmit antennas. With the further proviso that the total transmit power is increased proportionately to the number of transmit antennas, a linear capacity increase is achieved upon increasing the transmit power, which justifies the spectacular success of MIMOs. Hence we may argue that MIMO-aided transceivers and their cooperation-assisted distributed or virtual MIMO counterparts constitute power-efficient solutions. In a nutshell, since the conception of GSM in excess of three orders of magnitude bit-rate improvements were achieved in three decades, which corresponds to about a factor ten for each decade, because GSM had a data rate of 9.6 Kb/s, while HSDPA is capable of communicating at 13.7 Mb/s. However, the possible transmit power reductions remained more limited, even when using the most advanced multistage iterative detectors, since the required received signal power has not been reduced by as much as 30 dB. This plausible observation motivates the further research of advanced cooperation-aided wireless MIMO transceivers, as detailed in this treatise.

It is widely recognised that the choice of a specific bit-to-symbol mapping scheme or a beneficial constellation labelling is an influential factor, when designing bit-interleaved coded modulation using iterative decoding (BICM-ID) for the sake of achieving a high iteration gain. Generally, a larger constellation size of a higher-dimensional space renders the bit-to-symbol mapping design more flexible. In this paper, we first define a flexibility measure based on the extrinsic information transfer (EXIT) characteristics of bit-to-symbol mapping schemes. Secondly, we investigate the effect of expanding the constellation to a higher-dimensional space on our proposed EXIT characteristic flexibility index, when transmitting diverse numbers of bits per joint symbol.

The achievable performance of a jointly optimised iterative source and channel decoding (ISCD) arrangement invoking the Adaptive MultiRate Wideband (AMR-WB) speech codec is characterized, which exploits the intentional redundancy imposed by the proposed Over-Complete source-Mapping (OCM) scheme. The resultant OCM-aided AMR-WB bitstream is protected by a Recursive Systematic Convolutional (RSC) code and mapped to a Differential Space-Time Spreading (DSTS) arrangement using Sphere Packing (SP) modulation for transmission over narrowband temporally correlated Rayleigh fading channels. The effect of appropriately apportioning the total amount of redundancy between the source and channel codecs on the attainable system performance is demonstrated, while keeping the overall coding rate constant. The decoding convergence of the proposed scheme is studied with the aid of Extrinsic Information Transfer (EXIT) charts. Explicitly, our experimental results show that the specific scheme using a 2/3-rate channel encoder and a 3/4-rate OCM scheme exhibits an Eb/N0gain of 0.7 dB at the SegSNR degradation point of 1 dB, when compared to the system that assigns all the redundancy to the OCM scheme. By contrast, the scheme using a 3/4-rate channel encoder and a 8/9-rate OCM results in an Eb/N0gain of 1.0 dB.

This paper presents a novel multi-functional MultipleInput Multiple-Output (MIMO) scheme that combines the benefits of the Vertical Bell Labs Layered Space-Time (V-BLAST) scheme, of SpaceTime Codes (STC) as well as of beamforming. To further enhance the attainable system performance and to maximise the coding advantage of the proposed transmission scheme, the system is also combined with multi-dimensional Sphere Packing (SP) modulation. Additionally, further system performance improvements can be attained by serially concatenated convolutional coding combined with a Unity-Rate Code (URC) employed as an inner code. Then, at the receiver side, iterative decoding is invoked by exchanging extrinsic information between the three constituent decoders, i.e. the outer convolutional code's decoder, the inner URC's decoder as well as the SP demapper. Moreover, the convergence behaviour of the proposed scheme is evaluated with the aid of both three-dimensional (3D) and two-dimensional (2D) Extrinsic Information Transfer (EXIT) charts. Finally, we quantify the maximum achievable rate of the system based on EXIT charts and demonstrate that the iterative-detection-aided system is capable of operating within 0.6 dB from the maximum achievable rate limit. Explicitly, the proposed iteratively detected three-stage LSSTC-SP scheme is capable of attaining at least 4.8 dB gain at a BER of 10-5over the conventional iterativedetection aided two-stage scheme, where the extrinsic information is limited to the SP demapper and the outer code's decoder.

We present a novel tri-functional multiple-input multiple-output (MIMO) scheme that intrinsically amalgamates space-time spreading (STS), the Vertical Bell Labs Layered Space-Time (V-BLAST) scheme and beamforming with generalised multicarrier direct sequence code division multiple access (MC DS-CDMA). Further system performance improvements can be attained by employing channel coding, where the source bits are serial-to-parallel converted to two layers, each constituted by a serial concatenation of an outer code amalgamated with a unity-rate code for the sake of improving the convergence behaviour of the proposed system. Additionally, the convergence behaviour of the iteratively detected scheme is evaluated with the aid of extrinsic information transfer (EXIT) charts. We also propose a novel logarithmic likelihood ratio (LLR) postprocessing technique for improving the iteratively detected system's performance. Explicitly, after I = 10 decoding iterations and employing an interleaver depth of Dint= 160,000 bits, the proposed system supporting K = 4 users attains a BER below 10-5for Eb/Novalues in excess of -2.8 dB.

We propose a distributed turbo coding (DTC) scheme, where two users cooperate in a two-phase cooperation scenario constituted by the exchange of data between the users in the first phase followed by the uplink transmission of the two users' data in the second phase of cooperation. Following the information exchange phase, the data transmitted from the second user's transmitter during the second phase is an interleaved version of the first user's data. Each user's transmitter is equipped with a recursive systematic convolutional (RSC) code, an interleaver and a sphere packing (SP) mapper. At the receiver side, interference cancellation is employed, which outputs two branches of decoded data corresponding to the data transmitted from the two users' transmitters. Iterative detection is employed by exchanging extrinsic information between the RSC decoder and the SP demapper in each decoding branch, as well as between the RSC decoders in the two branches. The proposed DTC scheme is benchmarked against another cooperative scheme, where the two users do not exchange their data, they rather transmit their data simultaneously. At the receiver of the benchmark scheme, iterative detection is carried out by exchanging extrinsic information between the SP demapper and the RSC decoder of each user, but no iterations are invoked between the RSC decoders in the two branches. The proposed scheme attains an Eb/Nogain of about 25 dB at BER of 10-5, when compared to the benchmark scheme, while considering a perfect inter-user channel (IUC) and employing Isys=5 system iterations in conjunction with an interleaver depth of Dint=80, 000 bits. Additionally, we study the effects of both Gaussian as well as Ricean IUC on the achievable BER performance of the uplink DTC scheme.

A jointly optimised iterative source and channel decoding (ISCD) scheme invoking the Adaptive Multi Rate Wideband (AMR-WB) speech codec is proposed. More explicitly, the transceiver investigated consists of serially concatenated Recursive Convolutional (RSC) codes, a Unity Rate Code (URC) referred to as a precoder and the AMRWB speech codec, where the resultant bitstream is transmitted using Differential Space-Time Spreading (DSTS) and Sphere Packing (SP) modulation over narrowband temporally correlated Rayleigh fading channels. The convergence behaviour of the advocated scheme is investigated with the aid of Extrinsic Information Transfer (EXIT) charts, which suggests that potential performance improvements can be achieved by combining a serially concatenated precoder with the AMR-WB speech codec. The proposed system exhibits an Ef,/No gain of about 1.5 dB in comparison to the benchmark scheme carrying out iterative sourceand channel-decoding as well as DSTS aided SP-demodulation, but dispensing with the precoder, when using Isystem= 4 system iterations.

Recently, the turbo-detected sphere packing (SP) aided space-time block-coding (STBC) STBC-SP scheme was demonstrated to provide useful performance improvements over conventionally-modulated orthogonal design-based STBC schemes in the context of single-user multiple-input multiple-output (SU-MIMO) systems. Hence, in this letter, we extend its employment to the multiuser MIMO (MU-MIMO) scenario. For the sake of achieving a near maximum a posteriori (MAP) performance while imposing a moderate complexity, we specifically design theK-best sphere detection (SD) scheme for supporting the operation of the SP-modulated system, since the conventional SD cannot be directly applied to such a system. Consequently, with the aid of our modified SD, a significant performance gain can be achieved by the SP-modulated system over its conventionally-modulated counterpart in the context of MU-MIMO systems.

Conventional two-stage turbo-detected schemes typically suffer from a Bit Error Rate (BER) floor, preventing them from achieving infinitesimally low BER values, especially, when the inner coding stage is of non-recursive nature. We circumvent this deficiency by proposing a three-stage turbo-detected Sphere Packing (SP) aided Space-Time Block Coding (STBC) STBC-SP scheme, where a rate-1 recursive inner precoder is employed to avoid having a BER floor. The convergence behaviour of this serially concatenated scheme is investigated with the aid of 3D Extrinsic Information Transfer (EXIT) Charts. Furthermore, the capacity of the STBC-SP scheme is determined and an algorithm is proposed for calculating a tighter upper bound on the maximum achievable bandwidth efficiency, based on the EXIT charts of the STBC-SP demapper. The proposed three-stage turbo-detected scheme operates within about 1.0 dB of the capacity and within 0.5 dB of the maximum achievable bandwidth efficiency limit.

We present a novel multi-functional multiple-input multiple-output (MIMO) scheme, that combines the benefits of space-time codes (STC), of vertical Bell Labs layered space-time (V-BLAST) scheme as well as of beamforming. To further enhance the attainable system performance and to maximise the coding advantage of the proposed transmission scheme, the system is also combined with multi-dimensional sphere packing (SP) modulation. Additionally, we quantify the capacity of the proposed multi-functional MIMO aided multi-dimensional SP arrangement and propose a novel technique of computing an upper limit on the achievable bandwidth efficiency of the system based on extrinsic information transfer (EXIT) charts. Further system performance improvements can be attained by serially concatenating our proposed scheme with an outer code together with a unity-rate code (URC), where three different receiver structures are created by varying the iterative detection configuration of the constituent decoders/demappers. Moreover, the convergence behaviour of the proposed schemes is evaluated with the aid of EXIT charts. Explicitly, the three proposed systems are capable of operating within 0.9 dB, 0.6 dB and 0.4 dB of the maximum achievable rate limit. Additionally, the three stage assisted SP aided scheme is capable of outperforming its counterpart employing QPSK by 1 dB at a BER of 10-6.

Recently, the turbo-detected sphere packing (SP) aided space-time block-coding (STBC) STBC-SP scheme was demonstrated to provide useful performance improvements over conventionally-modulated orthogonal design based STBC schemes in the context of single-user multiple-input multiple-output (SU-MIMO) systems. Hence, in this treatise we extend its employment to the multi-user MIMO (MU-MIMO) scenario. For the sake of achieving a near maximum a posteriori (MAP) performance while imposing a moderate complexity, we specifically design the K-best sphere detection (SD) scheme for supporting the operation of the SP-modulated system, since the conventional SD cannot be directly applied to such a system. Consequently, with the aid of our modified SD, a significant performance gain can be achieved by the SP-modulated system over its conventionally-modulated counterpart in the context of MU-MIMO systems. For example, a performance gain of 3.5 dB can be achieved by the proposed 256-SP over the identical-throughput 16-QAM benchmark system in the scenario of a four-receive-antenna SDMA uplink (UL) system supporting two users both employing Alamouti's G2space-time code, given a target BER of 10-4.

In this paper we propose an iteratively detected Sphere Packing (SP) aided Differential Space-Time Spreading (DSTS) scheme using a Recursive Systematic Convolutional (RSC) code, for protecting the soft-bit assisted Adaptive Multi Rate Wideband (AMR-WB) decoder's bitstream, which is also protected by a novel over-complete source-mapping scheme. The convergence behaviour of the Multiple-Input Multiple-Output (MIMO) transceiver advocated is investigated with the aid of both three- dimensional (3D) and two-dimensional (2D) Extrinsic Information Transfer (EXIT) charts. The proposed system exhibits an Eb/Nogain of about 2.5 dB in comparison to the benchmark scheme carrying out iterative source- and channel-decoding as well as DSTS aided SP-demodulation, but dispensing with the over-complete source-mapping, when using Isystem= 3 system iterations.

A novel iteratively detected Sphere Packing (SP) modulation aided Orthogonal Frequency Division Multiplexing (OFDM) scheme is proposed, which we refer to as the SP- OFDM arrangement. The advocated SP-OFDM system outperforms conventional OFDM dispensing with SP. As its upper- bound performance limit, the Discrete Input Continuous Output Memoryless Channel (DCMC) capacity of this system is formulated. In order to maximize the DCMC channel capacity, a SP-to- OFDM-sub-carrier mapper (SPTSCM) is contrived, which is capable of providing an approximately 0.3 bit/s/Hz DCMC capacity benefit, by employing a variety of different SPTSCM arrangements. Additionally, the proposed SP-OFDM scheme exhibits a DCMC capacity advantage of 0.8 bit/s/Hz over the conventional equivalent-throughput Gray Mapping (GM) and Anti-Gray Mapping (AGM) based QPSK-OFDM schemes. Furthermore, the performance of the SP-OFDM system can be improved by serially concatenated convolutional coding relying on iterative extrinsic information exchange between the SP-symbol-to-bit demapper and the channel decoder. Explicitly, the proposed turbo-detected SP-OFDM scheme exhibits an approximately Eb/N0= 3 dB and Eb/N0= 4.5 dB gain at a Bit Error Ratio (BER) of 10-4over the equivalent- throughput turbo-detected GM based QPSK-OFDM scheme and AGM QPSK-OFDM scheme, respectively. EXtrinsic Information Transfer (EXIT) charts are employed for analyzing the achievable convergence behaviour.

A recently proposed space-time block coding (STBC) signal construction method that combines orthogonal design with sphere packing, referred to here as (STBC-SP), has shown useful performance improvements over Alamouti's conventional orthogonal design. In this contribution, we propose a purely symbol-based LDPC-coded scheme, demonstrating that the performance of STBC-SP systems can be further improved by concatenating sphere packing aided modulation with non-binary LDPC and by performing symbol-based turbo detection between the non-binary LDPC decoder and a rate-1 non-binary inner precoder. We also investigate the convergence behaviour of this symbol-based concatenated scheme with the aid of novel non-binary extrinsic information transfer (EXIT) charts. Finally, we demonstrate that in the investigated scenarios it requires 1-2 dB lower power in comparison to equivalent effective-throughput 0.5, 0.75 and 1 bit/symbol systems employing bit-based turbo detection.

Bandwidth efficient parallel-concatenated Turbo Trellis Coded Modulation (TTCM) schemes were designed for communicating over uncorrelated Rayleigh fading channels. A symbol-based union bound was derived for analysing the error floor of the proposed TTCM schemes. A pair of In-phase (I) and Quadrature-phase (Q) interleavers were employed for interleaving the I and Q components of the TTCM coded symbols, in order to attain an increased diversity gain. The decoding convergence of the IQ-TTCM schemes was analysed using symbol-based EXtrinsic Information Transfer (EXIT) charts. The best TTCM component codes were selected with the aid of both the symbolbased union bound and non-binary EXIT charts, for designing capacity-approaching IQ-TTCM schemes in the context of 8 PSK, 16 QAM, 32 QAM and 64 QAM modulation schemes.

This paper presents a novel turbo-detected multidimensional sphere packing (SP) modulation scheme using four transmit antennas combined with differentially encoded space-time spreading (DSTS). The DSTS scheme can be readily combined with PSK, QAM as well as SP modulation schemes. The SP-aided DSTS system advocated has low-complexity encoding and decoding algorithms that require no channel knowledge and it is capable of outperforming the DSTS system dispensing with sphere packing. Further system performance improvements can be attained by serially concatenated convolutional encoding combined with a unity-rate code (URC) referred to as a precoder. Then, at the receiver side, iterative decoding is invoked by exchanging extrinsic information between the precoder's decoder as well as the outer recursive systematic convolutional (RSC) code's decoder. Moreover, the convergence behaviour of the proposed system is evaluated with the aid of extrinsic information transfer (EXIT) charts. Explicitly, the turbo-detected precoded DSTS-SP system performs within 1.6 dB of the achievable multiple-input multiple output (MIMO) capacity. Finally, in contrast to an equivalent 0.5 bit/symbol throughput turbo- detected DSTS-SP scheme using no preceding, the turbo-detected precoded DSTS-SP scheme exhibits no error floor.

Conventional two-stage turbo-detected schemes typically suffer from a bit error rate (BER) floor, preventing them from achieving infinitesimally low BER values, especially, when the inner coding stage is of non-recursive nature. We circumvent this deficiency by proposing a three-stage turbo-detected sphere packing (SP) aided space-time block coding (STBC) STBC-SP scheme, where a rate-1 recursive inner precoder is employed to avoid having a BER floor. The convergence behaviour of this serially concatenated scheme is investigated with the aid of 3D extrinsic information transfer (EXIT) charts. Furthermore, the capacity of the STBC-SP scheme is shown and an algorithm is proposed for calculating a tighter upper bound on the maximum achievable bandwidth efficiency. The proposed three-stage turbo-detected scheme operates within about 1.0 dB of the capacity and within 0.5 dB of the maximum achievable bandwidth efficiency limit.

A multilevel coding (MLC) scheme invoking sphere packing (SP) modulation combined with space time block coding (STBC) is designed. The coding rates of each of the MLC component codes are determined using the so-called equivalent capacity based constituent-code rate-calculation procedure invoking a 4-dimensional (4D) sphere packing bit-to-symbol mapping scheme. Four different-rate Low-Density Parity Check (LDPC) constituent-codes are used by the MLC scheme. The performance of the resultant equivalent capacity based design is characterized using simulation results. Our results demonstrate an approximately 3.5 dB gain over an identical scheme dispensing with SP modulation. Furthermore although a similar performance gain is attained by both the proposed MLC scheme and its benchmarker, which uses a single-class LDPC code, the MLC scheme is preferred, since it benefits from the new classic philosophy of using low-memory, low-complexity component codes as well as providing an unequal error protection capability.

In this paper we consider serially concatenated and iteratively decoded irregular variable length coding (IrVLC) combined with preceded differential space-time spreading (DSTS) aided multidimensional sphere packing (SP) modulation designed for near-capacity joint source and channel coding. The IrVLC scheme comprises a number of component variable length coding (VLC) codebooks having different coding rates for the sake of encoding particular fractions of the input source symbol stream. The relative length of these source-stream fractions can be chosen with the aid of extrinsic information transfer (EXIT) charts in order to shape the EXIT curve of the IrVLC codec, so that an open EXIT chart tunnel may be created even at low Eb/N0values that are close to the capacity bound of the channel. These schemes are shown to be capable of operating within 0.9 dB of the DSTS-SP channel's capacity bound using an average interleaver length of 113,100 bits and an effective bandwidth efficiency of 1 bit/s/Hz, assuming ideal Nyquist filtering. By contrast, the equivalent-rate regular VLC-based bench- marker scheme was found to be capable of operating at 1.4 dB from the capacity bound, which is about 1.56 times the corresponding discrepancy of the proposed IrVLC-aided scheme.

Bandwidth efficient parallel-concatenated turbo trellis coded modulation (TTCM) schemes were designed for communicating over uncorrelated Rayleigh fading channels. A symbol-based union bound was derived for analysing the error floor of the proposed TTCM schemes. A pair of in-phase (I) and quadrature-phase (Q) interleavers were employed for interleaving the I and Q components of the TTCM coded symbols, in order to attain an increased diversity gain. The decoding convergence of the IQ-TTCM schemes was analysed using symbol-based extrinsic information transfer (EXIT) charts. The best TTCM component codes were selected with the aid of both the symbol-based union bound and non-binary EXIT charts for the sake of designing capacity-approaching IQ-TTCM schemes in the context of 8 PSK, 16 QAM and 32 QAM signal sets. It will be shown that our TTCM design is capable of approaching the channel capacity within 0.5 dB at a throughput of 4 bit/s/Hz, when communicating over uncorrelated Rayleigh fading channels using 32 QAM.

Jointly optimised iterative source- and channel-decoding is invoked for enhancing the error resilience of the adaptive multi rate wideband (AMR-WB) speech codec. The resultant AMR-WB coded speech signal is protected by recursive systematic convolutional (RSC) codes and transmitted using a sphere packing (SP) aided differential space-time spreading-/(DSTS) assisted transceiver. The performance of the proposed scheme is evaluated when communicating over correlated non-dispersive Rayleigh fading channels. The proposed system exhibits an Eb/N0gain of about 1 dB in comparison to the benchmark scheme carrying out joint channel decoding and DSTS aided SP-demodulation, but separate AMR-WB decoding, when using Iout= 4 external iterations.

In this contribution a novel adaptive differential space-time spreading assisted turbo detected sphere packing modulation scheme is proposed for improving the achievable throughput of code division multiple access (CDMA) systems. The scheme is capable of accommodating the channel signal-to-noise ratio (SNR) variation of wireless systems by adapting the system parameters. Explicitly, an adaptive transmission scheme constituted by a novel reconfigurable four transmit antenna aided arrangement using a variable spreading factor based differential space-time spreading scheme, as well as variable code rate recursive systematic convolutional codes is introduced. Our results demonstrate that significant effective throughput improvement can be achieved while maintaining a target bit-error-ratio of 10-4. Explicitly, when assuming an ideal Nyquist filter having a zero excess bandwidth, the system's effective throughput varies from 0.25 bits/sec/Hz to 16 bits/sec/Hz.

A signal construction method that combines orthogonal design with sphere packing has recently shown useful performance improvements over the conventional orthogonal design. In this contribution, we extend this concept and propose a novel Sphere Packing (SP) modulated differential Space-Time Block Coded (DSTBC) scheme, referred to here as (DSTBC-SP), which shows performance advantages over conventional DSTBC schemes. We also demonstrate that the performance of DSTBC-SP systems can be further improved by concatenating sphere packing aided modulation with channel coding and performing SP-symbol-to-bit demapping as well as channel decoding iteratively. We also investigate the convergence behaviour of this concatenated scheme with the aid of Extrinsic Information Transfer (EXIT) Charts. The proposed turbo-detected DSTBC-SP scheme exhibits a 'turbo-cliff' at Eb/No= 6dB and provides EbNogains of 23.7dB and 1.7dB at a BER of 10-5over an equivalent-throughput uncoded DSTBC-SP scheme and a turbo-detected QPSK modulated DSTBC scheme, respectively.

In this paper we design bandwidth efficient parallel-concatenated turbo trellis coded modulation (TTCM) schemes for communicating over AWGN and uncorrelated Rayleigh fading channels. The convergence properties of the symbol-based TTCM schemes employing various constituent codes, were analysed using symbol-based extrinsic information transfer (EXIT) charts. The traditional method used of generating EXIT charts is based on computationally complex multidimensional histogram measurements, which is only feasible for analysing TTCM schemes employing low-order modulation schemes, such as 4PSK and 8PSK. Hence, a novel low-complexity technique was employed in this paper for computing the symbol-based EXIT charts. Capacity-approaching TTCM schemes were designed based on the best constituent codes found when employing 8PSK, 16QAM, 32QAM and 64QAM modulation schemes.

A new multilevel coding (MLC) scheme invoking sphere packing (SP) modulation is proposed, where the SP arrangement is jointly designed with a space time block code (STBC) for the sake of attaining an additional space diversity gain. An iterative multistage decoding (MSD) aided multilevel sphere packing demodulator is proposed for attaining a high decoding performance at a low decoding complexity, when communicating over a correlated Rayleigh channel. The appropriate design of a 4-dimensional (4D) sphere packing bit-to-SP-symbol mapping scheme and the beneficial choice of the individual coding rates of the MLC scheme allows us to provide an unequal error protection capability, which is often required for efficient audio or video transmissions.

In this contribution, we propose a purely symbol-based LDPC-coded scheme based on a space-time block coding (STBC) signal construction method that combines orthogonal design with sphere packing, referred to here as (STBC-SP). We demonstrate that useful performance improvements may be attained when sphere packing aided modulation is concatenated with non-binary LDPC especially, when performing purely symbol-based turbo detection by exchanging extrinsic information between the non-binary LDPC decoder and a rate-1 non-binary inner precoder. We also investigate the convergence behaviour of this symbol-based concatenated scheme with the aid of novel non-binary extrinsic information transfer (EXIT) charts. The proposed symbol-based turbo-detected STBC-SP scheme exhibits a 'turbo-cliff' at Eb/N0= 5.0 dB and achieves an Eb/N0gain of 19.2 dB at a BER of 10-5over Alamouti's scheme

A novel differentially encoded space-time spreading (DSTS) scheme using two transmit antennas and Sphere Packing (SP) is proposed, which we refer to as the DSTS-SP arrangement. The advocated SP-aided system outperforms DSTS dispensing with SP and requires no channel knowledge. We also demonstrate that the performance of DSTS-SP systems can be further improved by serially concatenated convolutional coding and by performing SP-symbol-to-bit demapping as well as channel decoding iteratively. Explicitly, the proposed turbo-detected DSTS-SP scheme exhibits an Eb/Nogain of 17.0 dB at a bit error rate (BER) of 10-5over an uncoded identical-throughput system and an Eb/Nogain of 1.9 dB over the equivalent 2 bits/symbol effective throughput QPSK-modulated turbo-detected DSTS scheme

In this treatise we demonstrate, how a high spatial and frequency diversity can be achieved by combining differential space-time block coding (DSTBC) and fast frequency hopping (FFH). The proposed FFH assisted DSTBC scheme is capable of achieving a high diversity order given by the product of the frequency diversity order achieved by FFH and by the spatial diversity order offered by the DSTBC arrangement. Hence, the system is capable of exploiting the advantages of both DSTBC and FFH. Furthermore it is less vulnerable to some of their individual disadvantages, such as the performance degradation of DSTBC due to fast fading and the large bandwidth requirement of the FFH system. The proposed system also benefits from the employment of sphere packing and iterative turbo detection