Cooperative Transmissions for Random Access Wireless Networks with MPR Channels

A random access protocol for wireless networks was recently proposed in [16], that achieves high throughput by exploiting cooperative diversity of network nodes. According to that scheme, when a collision occurs, the network nodes bounce off the signal that they heard during the collision slot. The base station, by processing the collided packets and the relay transmissions can recover the collided packets. However, that approach was designed for a singlepacket reception (SPR) channel, where the capacity is one packet/time slot. In this paper, we propose a cooperative random access scheme for a channel with multi-packet reception (MPR) capability. The MPR channel is divided into multiple separate subchannels and each user is allowed to transmit multiple packets over different subchannels at the same slot. Packets transmitted on different subchannels can be separated without interfering to others. We propose schemes for resolving collisions on various subchannels in a way that we minimize the average processing time for each collided packet. We also demonstrate that the proposed approach fully exploits the channel capac-