Constant Delivery Delay Protocol Sequences for the Collision Channel Without Feedback
22 June 2017
We consider the collision channel without feedback, a time-slotted communication channel shared by K users. In this model, packets transmitted in the same time slot collide and are unrecoverable. Each users access the channel according to an internal periodical pattern called protocol sequence. Due to the lack of feedback, users cannot synchronize their protocol sequences, leading to unavoidable collisions and varying throughput. Protocol sequences that provide constant throughput regardless of delay offsets between users are called shift-invariant (SI), they have been studied and characterized in previous work. We propose a new class of SI sequences: Constant Individual Delivery Delay (CIDD) sequences which ensure that the delay between two successfully delivered packets is constant for each user. We present a characterization of CIDD sequences. We also prove that CIDD sequences can achieve the lower bound of SI sequences period but not the optimal throughput.
