Digital communications: fundamentals and applications
Digital communications: fundamentals and applications
Fundamentals of wireless communication
Fundamentals of wireless communication
WARP, a Unified Wireless Network Testbed for Education and Research
MSE '07 Proceedings of the 2007 IEEE International Conference on Microelectronic Systems Education
Zigzag decoding: combating hidden terminals in wireless networks
Proceedings of the ACM SIGCOMM 2008 conference on Data communication
Blind separation of two users based on user delays and optimal pulse-shape design
EURASIP Journal on Wireless Communications and Networking - Special issue on interference management in wireless communication systems: theory and applications
A new wireless network medium access protocol based on cooperation
IEEE Transactions on Signal Processing
Stability and delay of finite-user slotted ALOHA with multipacket reception
IEEE Transactions on Information Theory
Blind separation of two users based on user delays and optimal pulse-shape design
EURASIP Journal on Wireless Communications and Networking - Special issue on interference management in wireless communication systems: theory and applications
Hi-index | 35.68 |
A new scheme, namely ALOHA with Collision Resolution (ALOHA-CR) is proposed, which is a cross-layer approach for high throughput wireless communications in a cellular uplink scenario. Transmissions occur in a time-slotted ALOHA-type fashion but with an important difference: simultaneous transmissions of two users can be successful. In the beginning of each slot, users with non-empty queues contend with some probability after experiencing an intentional random delay. If more than two users transmit in the same slot, no attempt is made by the base station (BS) to separate the collision; the packets are discarded and the users are asked to retransmit at a later time. If one or two users transmit, then, depending on the state of the channel, the base station can recover the transmitted packets. The latter is achieved by oversampling the collision signal and exploiting independent information about the users that is contained in the signal polyphase components. The properties of the user intentional random delays are determined to maximize the probability of a second order collision being separable. The throughput of ALOHA-CR under both infinite and finite backlog assumptions is derived. Under the former assumption, the optimal contention probability is calculated to maximize the system throughput, while under the latter assumption, the region of stabilizing contention probabilities is determined based on the packet arrival rate. Queuing delay analysis for network users is also conducted. The performance of ALOHA-CR is demonstrated on the Wireless Open Access Research Platform (WARP) testbed containing five software defined radio nodes. The testbed results indicate that ALOHA-CR leads to significant increase in throughput and reduction of service delays as compared to ALOHA.