An n l (l n) space time block code (STBC) C over a complex signal set S consists of a finite number of n l matrices with elements from S. For quasi-static, flat fading channels a primary performance index of C is the minimum of the rank of the difference of any two matrices, called the rank of the code. C is of full rank if its rank is n and is of minimum delay if l = n. The rate R, in bits per...

The effect of two path interference on the symbol -error probability of binary coherent phase shift keyed (CPSK) receiving system is investigated. An expression for the probability of symbol error is derived to evaluate the system performance when a direct strong wanted signal is accompanied with two path interference and Gaussian noise.

In this paper, we present some novel results about the reliable information-rate supported by point-to-point multiple-antenna Rayleigh-faded wireless links for coded transmissions that employ two-dimensional (QAM or PSK) data constellations. After deriving the symmetric capacity of these links, we present fast-computable analytical upper and lower bounds that are asymptotically exact both for h...

In this paper, code pairs based on trellis coded modulation are proposed over PSK signal sets for a two-user Gaussian multiple access channel. In order to provide unique decodability property to the receiver and to maximally enlarge the constellation constrained (CC) capacity region, a relative angle of rotation is introduced between the signal sets. Subsequently, the structure of the sum alpha...

In this paper, we study a technique for using decision direction to extract digital signals from antenna array data. The algorithm alternates between 1) estimating and demodulating the received signals and 2) using the resulting bit deckions to regenerate the signal waveforms and recompute the beamformer wejghts. An analysis of the (asymptotic) symbol error rate performance of the algorithm for...

We consider a multiple antenna system when combined array processing with space–time coding is used. We present variable rate space–time block codes for two, three, and four transmit antennas and optimize the transmit power so that the average bit-error rate (BER) is minimized. Numerical results show that this optimum power allocation scheme provides significant gain over the equal power alloca...

In this letter, we provide an analysis of the performance of maximum likelihood detection (MLD) over flat fading channels in a wireless multiple input–multiple output (MIMO) antenna system. A tight union bound with an asymptotic form on the probability of symbol error rate (SER) for MIMO MLD systems with two-dimensional signal constellations (such as QAM and PSK) is introduced. Using this analy...

To achieve confidential communication channel between devices they must share a security association that defines the keys and algorithms used to secure the communication. In this paper, methods to create such security associations based on a pre-shared key used in WLAN and WiMedia’s UWB standards are discussed. The standards provide key agreement algorithms that operate on MAC layer based on a...