US 8,477,802 B2 · Slotted aloha congestion control

Abstract

A slotted Aloha communication system is provided according to one embodiment of the invention. The system may include a hub and a plurality of RCSTs. According to one embodiment, congestion control may occur at the RCST based in part on the number of segments received at the hub, the number of retransmission segments received at the hub and the number of successful collision retransmission segments received at the hub. The hub may communicate information regarding received segments. Congestion control may include calculating a transmission probably, performing a skewed probability measure with a probability equal to the transmission probability. If the results of the probability measure is positive the RCST may transmit or retransmit a segment within a first time prior, if the probability measure is negative then the RCST waits a set time period and reperforms the skewed probability measure.

Claims12

Dependent claims

A method for providing congestion control in a slotted Aloha communication system that includes a hub in communication with more than one RCST, the method occurring at an RCST comprising:

transmitting a first segment to the hub during a first timeslot;
receiving a segment detection bitmap from the hub, wherein the segment detection bitmap is received after the first segment is transmitted to the hub;
determining from the segment detection bitmap whether the first segment was not received at the hub due to a collision with another segment from another RCST that was successfully received, and asserting the successful collision flag in the first segment if the first segment was not received due to a successful collision;
and
retransmitting the first segment if the successful collision flag is asserted.

2 more elements

Dependencies are inferred from the claim text.

Slotted aloha congestion control

Life of this patent

Slotted aloha congestion control

Life of this patent

Abstract

Claims12