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In this paper, we analyze and simulate performance of space time block coded (STBC) binary pulse amplitude modulation-direct sequence (BPAM-DS) ultra-wideband (UWB) systems with double binary turbo code in indoor environments. The indoor wireless channel is modeled as a modified Saleh and Valenzuela (SV) channel, which is proposed as a UWB indoor channel model by IEEE 802.15.SG3a. From simulation...
In this paper, a wireless multicast scenario is considered in which the transmitter sends a common message to multiple client receivers in the presence of an eavesdropper. We are interested in protecting this common message against eavesdropping. Based on an information-theoretic formulation of the problem, in which the transmitter and the mutually independent multiple client receivers communicate...
In this work we investigate Multi-User Multiple-Input Multiple-Output (MU-MIMO) systems within the frame of an Orthogonal Frequency Division Multiplexing (OFDM) communication scheme. We look at the case where several User Terminals (UT), each of them having one transmit antenna, are grouped together and communicate in Up-Link (UL) with the Base Station (BS) equipped with two or four antennas. We perform...
A space-time coding scheme based on interleave division multiplexing (EDM) is investigated over an orthogonal frequency division multiplexing (OFDM) link that employs multiple transmit antennas. The performance of an iterative receiver structure for the proposed scheme over a quasi-static channel is evaluated via simulation, and its advantages are shown by comparison to other space-time schemes in...
In this paper, we address the implementation of FPGAs of Multi-Input-Multi-Output (MIMO) Decoder embedded in a prototype of 3G / 4G Mobile receiver This MIMO decoder is part of a multi-carrier code division multiple-access (MC-CDMA) radio system, equipped with multiple antennas at both ends of the link that is able to handle up to 32 users and provides raw transmission bit-rates up to 125 Mbps. The...
In this paper, we first consider a layered groupwise space-time block coding (GSTBC) scheme for multiple antennas communication systems. A novel list-based decoder for the GSTBC in multiple input single output (MISO) cases is then proposed. The error floor problem associated with the single receive antenna is resolved and, as a result, a near maximum likelihood (ML) performance is obtained. Our proposed...
In asynchronous wireless relay networks, the spacetime codes (STC) applied should be delay-tolerant. Although several delay-tolerant STC have been presented, they are limited by high decoding complexity, low rate and/or low diversity gain. To overcome these limitations, a new class of delay-tolerant STC, called shift group-decodable space-time block codes (STBC), with code rate 1 for arbitrary transmit...
The MIMO capacity for a single cell multiple-input and six outputs multiuser MIMO system is investigated. The channel model consists of an antenna array at each mobile terminal, the Rayleigh fading channel from the user to the base station, and also an antenna array at base station. The channel state information (CSI) is assumed to be always known at the base station, thus successive decoding for...
Multiple-Input Multiple-Output (MIMO) functionality has been shown to dramatically increase the capacity of wireless communication systems when the environment provides rich multipath scattering. In a predominantly Line-of-Sight (LOS) environment, the loss of diversity reduces the potential gain considerably. Recent studies have shown that systems which use a fully -polarimetric antenna such as triad...
This paper proposes a simple yet capacity-approaching concatenation of a mixture of short memory length convolutional codes and simple rate-1 block code followed by either complex 1-dimensional (1-D) anti-Gray or Gray mapping over multiple antenna channels with quadrature phase-shift keying (QPSK). By interpreting rate-1 code together with 1-D mapping as a multi-D mapping employed over multiple transmit...
We propose a new family of high-rate space-time block codes called embedded orthogonal space-time (EOS) codes. The family is parameterized by the number of transmit antennas, which can be any positive integer, and by the rate, which can be as high as half the number of transmit antennas. The proposed codes are based on a new concept called embedding, whereby information symbols of a traditional space-time...
In a protocol assisted switched diversity (PASD) system, the time separated repetition blocks are accumulated in order to increase decoding reliability. In this paper, we consider transmit antenna selection (TAS) protocols in a PASD system. To minimize system complexity we assume the feedback information is limited to the SNR of the current pair of antennas. We propose three TAS protocols : the random...
In this paper, we propose a method of constructing a novel generalized space-time code from a linear dispersion (LD) "protocode" by using the block spreading (BS) technique. The resulting generalized space-time code, therefore referred to as the BS-LD code, is shown to achieve the same rate, capacity, and performance as its protocode in flat fading channels. Moreover, our BS-LD codes exhibit...
This paper proposes a bit-interleaved coded transmission with multilevel modulation for multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems. In the proposed system, multiple layers are encoded and interleaved together, using one encoder and one interleaver, and then mapped by hierarchical symbol mapping. A corresponding receiver structure is presented, where...
In this paper, we propose a family of space-time block codes (STBC) that achieve full diversity when linear receivers, such as zero-forcing (ZF) or minimum mean square error (MMSE) receivers, are used. Our proposed STBC family is a combination/overlay between orthogonal STBC and Toeplitz codes, which can be viewed as a generalization of overlapped Alamouti codes (OAC) and Toeplitz codes recently proposed...
A partial interference cancellation (PIC) group decoding based space-time block code (STBC) design criterion was recently proposed by Guo and Xia, where the decoding complexity and the code rate trade-off is dealt when the full diversity is achieved. In this paper, we propose a systematic design of STBC that satisfy the criterion, i.e., achieve full diversity with the PIC group decoding for any number...
In classical non-iterative MIMO detection a soft-output MIMO detector computes likelihoods of the transmit bits being 1 or 0, given the received symbol vector. In iterative MIMO detection-decoding, detection performance is improved by exploiting apriori information about bit probabilities from the decoder. Transmit bits are viewed as random variables and the optimum detector performs Bayesian updating...
In forward link multiuser space-time block coded orthogonal frequency division multiplexing (STBC-OFDM) systems, the signal-to-noise power ratio (SNR) of each user's received signal is different from those of others. Thus, when subcarriers are not properly allocated to users, intensive bit errors occur in a specific user. This causes a burst error in such a user, and the number of correctable bits...
We consider a multiple-access multiple-input-multiple-output (MIMO) system with minimum mean square error successive interference cancellation (MMSE-SIC) receiver. Spatial multiplexing is employed with some of the users having target-rate requirements while other users are working with best-effort data rates. We show that the best-effort users can achieve higher rates when the data streams of any...
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