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The paper is devoted to the implementation on the FPGA of the algorithm for the optimal combining of signals. Described the algorithm, the architecture of the optimal combining block, implemented to a four-element antenna system. The signal-to-noise ratio chosen as a criterion reflecting the efficiency of interference suppression in the reception band (increase of noise immunity). The effectiveness...
With the advent of new technologies every day and with each technology more bandwidth intensive than the previous, The need for some transformative technology to coop with the bandwidth problem is ever growing. The current technologies like LTE uses MIMO, OFDM and coding techniques that have reached their limits and provide an almost theoretical efficiency but they also in the near future may be uanble...
A compact range wireless access system in the 60 GHz-band has been proposed for multi-Gb/s data transfer. A prototype GATE (Gigabit Access Transponder Equipment) was made to evaluate the coverage as well as the system performance of received power, bit-error rate (BER) and signal-to-noise ratio. Originally, the double-layer corporate-feed waveguide slot arrays with different number of elements were...
We present an analytical approach for determining the signal-to-noise-ratio (SNR) of m multiple antennas in the line-of-sight case. The antennas are placed at random positions within a disc of given diameter d. We characterize the angular signal strength with three sectors: the main beam, the side beams and an area of white Gaussian noise. The SNR and the sector angles depend on d, m, and the wavelength...
Multiple input multiple output (MIMO) communication architecture has spectral efficiencies far beyond those offered by conventional techniques, and is greatly to increase the channel capacity. In this paper, we investigate the MIMO channel capacity in correlated channels using the uniform angular distribution, numerical simulations are performed with Matlab to verify the proposed formula. We prove...
In this paper, we propose a Minimum Bit Error Rate (MBER) beamforming combined with Space-Time Block Coding (STBC) according to the number of antenna array. A class of adaptive beamforming algorithm has been proposed based on minimizing the BER cost function directly. Consequently, MBER beamforming is capable of providing significant performance gains in terms of a reduced BER. The beamforming weights...
This paper investigates the power allocation algorithms based on convex theory for multiuser multi-relay amplify-and-forward (AAF) wireless cooperative network. In this system, there are multiple single-antenna users to communicate with one destination with the help of multiple relay nodes at the same time. In order to guarantee the quality-of-service (QoS) for all the users and reduce the power consumption,...
In this paper, an analytical framework is developed for the performance analysis of three transmit antenna selection (TAS) strategies for dual-hop multiple-input multiple-output channel-assisted amplify-and-forward (CA-AF) relay networks over Rayleigh fading. The cumulative distribution function of a lower bound of the end-to-end signal-to-noise ratio (SNR) of the optimal TAS strategy is derived and...
To deal with the short burst signals' combining problem at low Signal-to-Noise Ratio (SNR) in an antenna array, this paper presents a novel combining weights estimate algorithm, called CM-WE, which based on the information mining of the array signals' correlation matrix. Then, it compares CM-WE's performance with SUMPLE algorithm which is commonly used in the Deep Space Network (DSN). Simulation shows...
By using frequency-domain oversampling at the receiver, we propose a novel blind channel estimation scheme for multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems. Specifically, a subspace blind channel estimation approach is developed, based only on second-order statistics of the received signal. The estimated MIMO channel is nicely determined by Nt minimum...
High-rate space-time block coding scheme is constructed for multiple-input multiple-output (MIMO) Rayleigh fading channels. It employs the D-blast transmission scheme combined with lattice constructions tailored for the number of transmit and receive antennas, transmission rate and signal-to-noise ratio. The lattices are constructed with the aid of performance-optimizing criteria, and the obtained...
In this paper, the rate region of the two user MIMO broadcast channel (BC) with linear filtering at high signal-to-noise ratio (SNR) is studied when time sharing is not available and the transmitter has fewer antennas than the sum of the receiving antennas. To reach the boundary of the rate region, the sum rate is maximized subject to a rate ratio constraint. Furthermore, the sum rate is approximated...
Outage analysis of cooperative space-time block coding (STBC) multiple-input multiple-output (MIMO) relaying system with a single relay is discussed in this paper. The source node, equipped with two transmit antennas, broadcasts each STBC code to the relay and the destination nodes. Then, the relay node also equipped with multiple antennas, amplifies-and-forwards (AF) the received STBC codes. Finally,...
The fundamental diversity-multiplexing tradeoff (DMT) of the quasi-static fading, symmetric 2-user MIMO interference channel (IC) with channel state information at the transmitters (CSIT) and a short term average power constraint is obtained. The general case is considered where the interference-to-noise ratio (INR) at each receiver scales differently from the signal-to-noise ratio (SNR) at the receivers...
This paper analyzes selection diversity as an effective tool to combat channel impairments in relay-assisted cellular systems. We consider the downlink scenario where the base station equipped with N antennas transmits to the mobile station either directly, or indirectly via a relay station, according to the link with the strongest received signal-to-noise ratio (SNR). For this system, we analyze...
Although multiple antenna and cooperative communication techniques can increase the system capacity, it can be difficult to use them in practice because of their high complexity. In this paper,” joint transmit/receive antenna and relay selection” is proposed to keep the bit error rate and complexity low in cooperative communication. It is assumed that there are multiple users with multiple antennas...
Upper bounds on link spectral efficiency of amplify-and-forward cooperative diversity networks with independent but non-identically distributed wireless fading statistics are studied by deriving the Shannon capacity of three distinct adaptive source transmission techniques: (i) constant power with optimal rate adaptation (ORA); (ii) optimal joint power and rate adaptation (OPRA); and (iii) fixed rate...
The presence of line-of-sight (LoS) components is usually regarded as a limiting factor for multiple-input multiple-output (MIMO) systems due to the lower multiplexing gains compared to the prevalent independent and identically (i.i.d.) Rayleigh fading model. In this paper, we present a versatile methodology for maximizing LoS-MIMO capacity at any operating signal-to-noise ratio (SNR) by capitalizing...
Recently, pre-fast Fourier transform (pre-FFT) combining has been introduced for space-time block-coded (STBC) orthogonal frequency division multiplexing (OFDM) systems. Despite the complexity reduction, the resultant signal-to-noise ratio (SNR) values of different subcarriers are often not balanced, and it limits the system performance. In this paper, we propose to use the max-min fair criterion...
A multiple-antenna Gaussian wiretap channel in which the number of antennas at the source is not larger than that at the eavesdropper is considered. Without feedback, the secrecy capacity over such a channel generally converges to a constant at high signal-to-noise ratio (SNR). A half-duplex secure protocol allowing the destination to actively broadcast random keys over insecure channels is proposed...
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