A MAC Protocol for Half-Duplex Multi-Packet Detection in SC-FDE Systems

2010 IEEE Wireless Communication and Networking Conference

Dinis

et al. 2010

Self Cite

This paper deals with multi-packet detection for SC modulations (Single-Carrier) with FDE (FrequencyDomain Equalization). We consider iterative frequencydomain receivers that jointly perform equalization, multipacket separation and channel decoding operations, for up to Q max mobile terminals transmitting in one slot.In this paper we propose an accurate analytical model for a p-persistent random access MAC protocol, designed to handle a total number of mobile terminals J above Q max . It evaluates the uplink non-saturated packet delay and calculates the optimal configuration for the packet transmission probability associated to each mobile terminal that minimizes the delay. Our analytical results are validated using physical and MAC layer simulations. 1

“…It can be seen that (9) is equivalent to the saturation throughput, S sat , in [8]. In saturation all MTs always have a packet to transmit (χ J = 1).…”

Section: B Epochmentioning

confidence: 99%

Section: Optimizationmentioning

confidence: 99%

Section: Simulationsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Delay Optimization on a p-Persistent MAC Protocol for a Multi-Packet Detection in SC-FDE System

2010 IEEE Wireless Communication and Networking Conference

Dinis

et al. 2010

Self Cite

Energy Efficient NDMA Multi-packet Detection with Multiple Power Levels

Ganhao

Technological Innovation for Sustainability

et al. 2011

Multi-packet detection approaches handle packet collisions and errors by forcing packet retransmission and by processing the resulting signals. NDMA (Network Diversity Multiple Access) detection approach forces Q retransmissions by all stations when Q stations transmit in one collision slot. Previous work assumed that perfect power control is used, where the average reception power is equal for all stations. In this paper we handle the scenario where no power control is used, and multiple power levels are received. We propose a modification to the basic NDMA (Network Diversity Multiple Access) reception mechanism, where some of the stations may not retransmit its packets all the times. This paper evaluates the EPUP (energy per useful packet) and the goodput for a saturated uplink. Our analytical results are validated by simulation using joint PHY (physical layer) and MAC (Medium Access Control) behavior. We show that by suppressing some retransmissions we are able to improve the system's EPUP, practically without degrading the network goodput.

On the use of frequency-domain cross-layer diversity techniques to cope with lost packets

Dinis

et al. 2013

Physical Communication

The Quality of Service (QoS) requirements for modern broadband wireless systems can be very high, with small error rates and delays. To preclude significant degradation on the spectral efficiency, these systems also require high throughputs. Lost packets, either due to errors or collisions, are usually discarded and need to be retransmitted, leading to performance degradation. An efficient alternative to simple retransmissions is to combine the signals associated to different transmission attempts. This paper analyses two time diversity approaches to cope with lost packets that are relatively similar at physical layer but treat different packet loss causes: a low-complexity diversity combining ARQ scheme (Automatic Repeat reQuest) employed in a TDMA (Time Division Multiple Access) architecture; and a Network Diversity Multiple Access (NDMA), which is a multi-packet reception approach able to separate multiple mobile terminals transmitting simultaneously in one slot using temporal diversity. This paper combines the use of these techniques in Single Carrier Frequency Domain Equalization (SC-FDE) systems, which are widely recognized as the best candidates for the uplink of future broadband wireless systems. It aims to present a comparison among the approaches focusing on error rate, throughput and delay performances, not discarding the implementation complexity issues.