Method to bootstrap into a frequency agile ad hoc network of radios that use a non-deterministic frequency pattern

摘要

A method to facilitate late entry of a late entrant node into an ad-hoc radio network involves accessing from a memory at the late entrant node an initial frequency hopping sequence for the ad-hoc radio network. The late entrant node uses at least the initial frequency hopping sequence to determine a first frequency to monitor during a communication epoch corresponding to one of the frequency hops. The late entrant node thereafter monitors the first frequency to detect the presence of a beacon signal transmitted by a participating node of the network. Subsequently, the late entrant node determines a second frequency included in the current hopping sequence of the network based on information contained in the beacon signal.

主权项

1. A method for facilitating late entry of a late entrant node into an ad-hoc radio network in which a network hopping sequence changes over time in a non-deterministic manner in response to a spectral environment, comprising:
accessing from a memory at the late entrant node an initial frequency hopping sequence for said ad-hoc radio network, said initial frequency hopping sequence specifying a plurality of frequencies, each respectively assigned to one of a plurality of defined frequency hops of said frequency hopping sequence, said initial frequency hopping sequence specifying a sequence of frequency hops used by the ad-hoc network at a time corresponding to initiation of the ad-hoc network; at a time after said initiation when the initial frequency hopping sequence has migrated in a non-deterministic way to a current frequency hopping sequence different from the initial frequency hopping sequence, and unknown by the late entrant node, discovering the current frequency hopping sequence by exclusively monitoring at least a first frequency specified by the initial frequency hopping sequence; if the presence of a signal transmitted by a participating node of said ad-hoc network is not detected on at least the first frequency as a result of the exclusive monitoring, iteratively monitoring one or more alternate frequency values in accordance with an ordered list respectively specified for at least the first frequency until detecting the presence of the signal, said signal comprising
(1) first information concerning at least one “next+M” hop frequency of the current hopping sequence of said ad-hoc network, where M is an integer having a value equal to or greater than zero, and(2) second information useful for determining a time when the at least one next+M hop frequency will be used by nodes of said ad-hoc network; and determining a second frequency included in said current hopping sequence of said network based on the first information contained in said signal.