Frequency-hop signaling and multiple packets per transmission for store and forward packet radio networks

Store and forward packet radio networks often must be able to forward a packet through several radios to be able to deliver the packet to its destination. Forwarding protocols are required to control the relay of packets, and the protocols must account for the high variability of the qualities of the links and the unique characteristics of frequency-hop spread-spectrum signaling. The authors investigate one aspect of the forwarding protocol that allows multiple packets to be included in each transmission attempt. The capture property of frequency-hop signaling and the behavior of store and forward packet radio networks are exploited in the design of protocols that permit multiple-packet transmissions. In general, a potential tradeoff arises because the use of multiple packet transmissions can increase the throughput, but it can also increase the delay. In certain situations, however, the delay is decreased with the use of multiple-packet transmissions, or at least the increase in delay is not too great. Two new transmission protocols that employ multiple-packet transmissions are described, and their performance is evaluated in a store and forward packet radio network simulation