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In this paper, we propose a new algorithm for jointly processing a set of Hermitian matrices. It is called structured joint congruence (STJOCO) transformation. Instead of simultaneously diagonalizing a set of matrices, the STJOCO transformation finds a non-singular matrix which jointly minimizes the squared magnitude of the off-diagonal elements in the ith row and the ith column of the ith matrix...
We study the two-user one-eavesdropper discrete memoryless compound wiretap channel, where the transmitter sends a common confidential message to both users, which needs to be kept perfectly secret from the eavesdropper. We provide a new achievable secrecy rate which is shown to be potentially better than the best known lower bound for the secrecy capacity of this compound wiretap channel. We next...
We derive a sufficient condition for a square FIR MIMO system to have a causal and stable IIR inverse. The condition requires that the spectral norm of the normalized channel impulse response (i.e., the first tap is the identity matrix) is below a certain bound. Intuitively, this means that the system has a strong first tap. This condition often is easier to check than the usual minimum-phaseness,...
The following topics are dealt with: information theory; coding; MIMO systems; OFDM systems; antennas; telecommunication channels; relaying; channel estimation; protocols; wireless networks; resource management; beamforming; and multiuser systems.
A Rate-Compatible Punctured Convolutional (RCPC)-encoded Vertical Bell Laboratories Layered Space-Time (V-BLAST) MIMO system to provide a robust wireless communication link is proposed. The V-BLAST detection is based on Minimum Mean-Squared Error (MMSE) criterion, to alleviate the noise enhancement commonly found in the original V-BLAST scheme based on Zero Forcing criterion. Different code rates...
This paper deals with bit-loading techniques for a multiple-input multiple-output bit-interleaved coded orthogonal frequency division multiplexing (MIMO BIC-OFDM) system. The per-stream coded bit loading algorithm is proposed based on a spatial domain power adaptation. For each spatial stream, a different power constraint is assigned using an initial power allocation (IPA) combined with the residual...
We present iterative algorithms which efficiently compute an optimized subset of equiprobable input symbols that achieves near-capacity on a large asymmetric discrete memoryless channel (DMC). The optimized subset defines a delay-free channel-adapted inner code which can be combined with a standard code. The introduction of a dense data structure renders it possible to apply channel-adaptive coding...
Emerging multiple-input multiple-output (MIMO) systems are regarded to play a key role in 4G wireless systems in order to achieve higher data rate while maximizing spectral efficiency. This paper presents a proficient hardware realization of MIMO systems that is designed and implemented on a Xilinx Virtex™-4 XC4VLX60 Field Programmable Gate Arrays (FPGA) device. The MIMO encoder implementation is...
The investigation of transmission capacity of MIMO mobile communication system designed on principles of multipath effect has been carried out. Spatial encoding is realized by the beamforming method. Power distribution along transmit and receive antennas is specified by the principle of “water-filling”.
We study optimized video transmission using a wireless Multiple Input Multiple Output (MIMO) system and partial channel state information at the transmitter. The optimization consists of choosing the coding parameters of the video encoder depending on the pairs of used rates and corresponding outage probabilities of the MIMO channel. We perform simulations and compare N×N MIMO system performance to...
In this paper, we consider amount of feedback and resource allocation for a downlink in MIMO-OFDMA system. The amount of feedback data increases with the number of user, subcarrier, antenna numbers rise. In order to limit the feedback date in a fix level, a prefixed threshold based feedback is proposed. The value of CSNR is feedbacked only when the channel gain is greater than the threshold. Simulation...
This paper provides the performance analysis of Multi Input Multi Output (MIMO) Multi carrier (MC) interleaver based multiple-access system with multiuser detection. Interleave-division multiple access (IDMA) is a scheme in which users are separated by employing different interleavers instead of different signatures as in a conventional code-division multiple-access (CDMA) scheme. The basic principle...
This paper studies six half-duplex cooperative relaying schemes with one multi-hop beamforming scenario in the 60 GHz band. Five of them are known. One new scheme is modified based on superposition coding. Under this scenario, we make the achievable rate expressions of the studied relaying schemes. By using these expressions, the comparison is made in terms of achievable rate versus relay-node position...
For the off-wire dustings of connection the negative consequences of stoppings beating of signal, waves caused multiband distributions are considered. The features of set about a reception, realized by the use of a few aerials on a receiving side are considered. Comparison of different methods of combining of initial signals of separate aerials is conducted and recommendations are given from their...
Multiple antenna systems are a promising approach to increase the data rate of wireless communication systems. There exist two main transmission schemes. In BICM systems, modulated symbols are multiplexed on multiple transmission antennas while an outer error correction code ensures the desired quality of service for a given data rate. Space-time trellis codes use a trellis structure to determine...
This paper deals with a design of next generation Gigabit WLAN system based on IEEE802.11TGac's functional requirements. It achieves 1.1 Gbps throughput for 45 meter propagation distance with 80 MHz bandwidth on 5 GHz band. The proposed preamble ensures backward compatibility with the IEEE802.11a/n systems and has lower PAPR and comparable preamble efficiency with IEEE802.11n's preamble. It uses MIMO...
The performance of a wireless communication system is analyzed considering multi-carrier OFDM with Multiple- Input-Multiple-Output (MIMO) wireless channel and Space-Time Block Coding (STBC). Bit Error Rate (BER) expression for MIMO-OFDM system without and with STBC is presented considering fading and timing jitter with QPSK, DPSK and DQPSK modulation schemes. The performance results are evaluated...
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...
We present a new transmission scheme which apply the linear dispersion code (LDC) to a single transmit antenna in the OFDM system. Our scheme, named virtual LDC, transfers the LDC substreams through the multiple uncorrelated OFDM subchannels. The virtual LDC scheme can achieve the coding and diversity advantage as well as LDC in MIMO. It is shown that the virtual LDC scheme can improve the BER performance...
Alamouti scheme provides a diversity gain no more than 2 over time-selective fading channels under the circumstances of 2??1 MIMO. A full-rate space-time code, space-time codes for time-selective fading (STC-TS), is proposed to provide more diversity gain when the channels fade fast. While the transmission lasts 2N (N>1) symbol periods, the diversity gain is almost 2N. What's more, the optimization...
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