Zuojun Wang

Noncooperative distributed MMSE relay schemes under jamming environment and node geometry in wireless relay networks

The main contribution of this paper is the derivation of optimum relay amplifying matrices for noncooperative distributed wireless amplifying-and-forward relay networks. Channels connecting any two nodes are under fading, and either partial-band noise jamming or non-symmetrical node geometry. The minimum mean squared error criterion is used for the optimality. With the derived optimum relay amplifying matrices, the bit error rate is compared through simulation for various situations.

Node geometry and broadband jamming in noncooperative relay networks under received power constraint

This paper presents node geometry and broadband jamming in noncooperative wireless relay networks under the received power constraint. Diagonal relay amplifying matrices based on minimum mean square error (MMSE) criteria corresponding to node geometry and broadband jamming in wireless networks under the received power constraint are derived. All relay nodes are assumed not to communicate with their received signals for no cooperation. N relay nodes and one-source-one-destination node pair for amplify-and-forward (AF) strategy are employed. Bit error rate of the wireless relay network using the derived diagonal relay amplifying matrices is presented.

Broadband Jamming and Channel Uncertainty for Noncooperative Wireless Relay Networks under Received Power Constraint

This paper presents a non cooperative distributed minimum mean square error (MMSE) relay scheme. It is designed for wireless relay networks based on an amplify and forward (AF) strategy for one-source, one-destination pair and N relay nodes. Both broadband noise jamming and channel uncertainty were studied in a wireless relay network under received power constraint. The main contribution of this paper is the derivation of the MMSE-based diagonal relay amplifying matrix in wireless relay networks under both broadband jamming and channel uncertainty. Effects of jamming and channel uncertainty using the derived diagonal relay amplifying matrix were evaluated. Bit error rate (BER) performance was investigated using Monte-Carlo simulations.

Effects of Node Geometry on Noncooperative Distributed SIMO Wireless Relay Networks

In practice, in any wireless network where 1-source, N-relays and M-destinations exist, each relay node will most likely have different separations with the source and any destination. Therefore, relay node geometry effect in a single-input multiple-output (SIMO) system was studied in this paper. The main contribution of this paper is the derivation of an optimal diagonal amplifying relay matrix under node geometry effect. This matrix is designed for a non cooperative distributed wireless relay network. The effect of node geometry in wireless relay networks was studied. The new derived matrix was evaluated using bit error rate (BER). Also, performance comparisons with/without no node geometry were a focus in our study.

Amplifying Matrix Design for Distributed Noncooperative SIMO Wireless Relay Networks under Jamming Environment

The main contribution of this paper is the derivation of an optimal diagonal amplifying relay matrix. This matrix is for a non cooperative distributed wireless relay network in a jamming environment. Minimum mean square error (MMSE) criterion was used in this study. Jamming location was also studied in this paper. Results show that diversity of a system can be degraded or even get lost depending on jamming location. A single-input multiple-output (SIMO) system strategy was implemented, using one-source, M-destination and N-relay nodes. System performance for the new derived matrix was evaluated using bit error rate (BER). Also, performance comparisons with/without jamming were a focus in our study.

Noncooperative Distributed Wireless Relay Networks under Channel Uncertainty and Power Constraint

This paper derives an optimum relay amplifying matrix for a wireless relay network under channel uncertainty and received power constraints at the destination node. To achieve this objective, an amplify-and-forward strategy is employed at the relay nodes, and the minimum mean square error (MMSE) criteria is applied. And, for simplicity, this paper will assume a one-source-one-destination pair and N multiple relays. Then this paper will compare the bit error rate (BER) performance of the proposed relay network with that of other existing schemes, and also claim that the proposed relay amplifying matrix can improve BER significantly, compared to other existing schemes.

Amplifying matrix design for noncooperative SIMO relay networks under channel uncertainty

This paper presents an optimum diagonal amplifying relay matrix based on minimum mean square error (MMSE) criterion for noncooperative distributed wireless relay networks under channel uncertainty. A single-input multiple-output (SIMO) system with one-source M-destination N-relay nodes is considered. Bit error rate (BER) of the wireless relay network under both certain and uncertain channel conditions is simulated using the derived optimum diagonal amplifying relay matrices. For comparisons, the case of both perfect and imperfect channel conditions for single-input single-output (SISO) system with N relay nodes is also considered.

Automatic cycle identification in tidal breathing signals

In this paper, we introduce a novel cycle identification algorithm using MATLAB programming to automatically identify cycles in tidal breathing signals. The algorithm was designed in four steps using filtering, derivation, and other signal processing techniques. To verify the accuracy of the proposed algorithm, its results were compared with those of cycles identified manually by a human coder. Simulations results showed that despite the complexity of respiratory signals, the proposed algorithm could identify cycles more accurately than the human coder. This algorithm could serve as an important first step toward timely identification and coding for more complex respiratory signals, such as those underlying speech productions.

MMSE-Based amplifying relay matrix for noncooperative AF wireless relay network under power constraints

This paper derives analytically an optimum amplifying relay matrix using the minimum mean square error (MMSE) criteria for a noncooperative amplify-and-forward (AF) distributed relay network. Global and local power constraints are included in the analysis. And a one-source-one-destination node pair and N-relay network is considered. Because the relays are noncooperative, this paper exploits the diagonal property in an amplifying relay matrix for the optimum matrix derivation. Then, this paper claims that the bit error rate of the AF network using the proposed amplifying relay matrix is significantly better than that of the AF network with the other existing amplifying matrices.