1 research outputs found
Performance of Hybrid ARQ for NDMA Access Schemes with Uniform Average Power Control
Traditionally, a packet with errors, either due
to channel noise or collisions, is discarded and needs to
be retransmitted, leading to performance losses. Network
Diversity Multiple Access (NDMA) handles collisions by
combining a multipacket detection scheme with time diversity.
In NDMA, the Base Station (BS) forces mobile terminals
(MTs) to transmit P copies of each packet when P MTs
collide. Diversity combining is limited to P copies of the
packets, not allowing it to adapt to severe errors due to
channel noise. This paper considers a multipacket detection
scheme recently proposed, which reduces the Packet Error
Rate (PER) when more than P packet copies are available.
In this paper, a Hybrid-ARQ NDMA (H-NDMA) access
mechanism is proposed. The access mechanism forces MTs
with reception errors during a collision resolution epoch
to transmit more than P times. Analytical models for
Poisson traffic are proposed for the throughput and delay.
The proposed system’s performance is evaluated for a
Single-Carrier with Frequency Domain Equalization (SCFDE)
scheme, and compared to classical NDMA. H-NDMA
parameter configuration is defined in terms of Quality of
Service (QoS) requirement