Method of sensing in a radio system employing opportunistic spectrum access

摘要

In a radio system where wireless nodes are in contact, the wireless nodes are enabled to exchange information with adjacent nodes. In addition, distant nodes out of range for direct communication can be communicated with by forwarding data over multiple hops. The wireless nodes are configured to perform sensing of at least one radio resource. A node can be adapted to combine the sensing measurement data into a sensing result, such as an estimate of the probability of whether the resource is free or not. The sensing performed in a node is distributed to at least one other wireless node. Each wireless node can, therefore, access sensing information from at least one other wireless node located in the vicinity of the wireless node. Based on the collective information from at least one other node, a wireless node can make an improved decision if a particular radio resource is free to use or not.

主权项

1. A wireless node for use in a radio system, the wireless node being configured to be in contact with and exchange information with other wireless nodes of the radio system, comprising:
means for performing sensing of at least one radio resource; means for exchanging information with adjacent ones of the wireless nodes; means for distributing an outcome of the sensing of the at least one radio resource to at least one other of the wireless nodes; means for receiving an outcome from a sensing of at least one radio resource performed by another one of the wireless nodes, and means for determining if a particular radio resource is free to use based on collective sensing information including the outcome from the sensing performed by the another one of the wireless nodes, and wherein the wireless node is configured to communicate information by forwarding data over multiple hops; wherein the outcome of the sensing of the at least one radio resource performed by the wireless node has a geographic validity associated therewith; wherein the collective sensing information is weighted based on times that the sensing was performed such that more recent sensing information is given greater weight than older sensing information in determining if the particular radio resource is free; wherein the wireless node is configured to forward sensing information received from one of the wireless nodes to another one of the wireless nodes; and wherein the wireless node is provided with a limit on forwarding the sensing information based on whether the wireless node has knowledge of its geographic location and the geographic location of the another one of the wireless nodes such that the sensing information is forwarded only within a geographic boundary defined by the geographic validity associated with the outcome of the sensing.