Optimal Transmission Method in Cooperative Relay Communication Systems with Hierarchical Modulation

16-QAM Hierarchical Modulation Optimization in Relay Cooperative Networks

Relay Selection Considering Successive Packets Transmission in Cooperative Communication Networks

Relay selection has been regarded as an effective method to improve the performance of cooperative communication system. However, frequent operation of relay selection can bring enormous control message overhead and thereby decrease the performance of cooperative communication. To reduce the relay selection frequency, in this paper, we propose a relay selection scheme to choose the best relay w...

Performance Enhancement Scheme Using Hierarchical Modulation in Cooperative Communication

In this paper, a decode-and-forward cooperative communication system using hierarchical modulation (HM) to improve bit error probability (BER) performance is proposed. A HM symbol has high priority (HP) and low priority (LP) data streams that have different levels of BER. In the proposed scheme, all decoded symbols are treated as HP symbol by suitable design for cooperative communication. Conse...

Quasi-optimal grouping for broadcast systems with hierarchical modulation

Recently, we proposed to combine time sharing with hierarchical modulation to increase the transmission rate of broadcast systems. Our proposal involves to group the receivers in pairs in order to transmit with hierarchical modulation. We introduced several grouping strategies but the optimal matching remained an open question. In this letter, we show that the optimal grouping is the solution o...

Transmission Systems Exact symbol error probability of cooperative systems with partial relay selection

In this paper, we derive the exact symbol error probability (SEP) of cooperative systems using amplify and forward (AF) relaying and partial relay selectionwhen the different links are independent and non-identically distributed. In conventional relay selection, the selected relay offers the best instantaneous signal to noise ratio (SNR) of the relaying link (source-relay-destination). However,...