Patent ID: 8085683

Claim:
A method for determining a metric for link quality between a first node and a remote node of a wireless network, said nodes communicating using a handshake protocol in which said first node expects to receive an acknowledgement (ACK) of receipt of a data packet from said remote node, said method comprising the steps of: providing a measure for any combination of: a) noise-related losses (pn) between said first and remote nodes, b) collision induced losses (pc) between said first and remote nodes, c) hidden-node losses (ph) between said first and remote nodes, d) a slot being erroneously detected as busy when a successful transmission could have been made (pexp) between said first and remote nodes, and e) a probability of successful reception of a packet when a collision occurs (pplc) between said first and remote nodes, at least one of said combined measures being based on a number (A) of acknowledgements received from said remote node vis-à-vis a number (T) of packets transmitted to said remote node; and using said measure to determine said link quality metric between said first node and said remote node; wherein said nodes communicate using an IEEE 802.11 protocol and providing said measure comprises: measuring a collision induced loss probability pc as pc=1−(T 1 ·A 0 )/(T 0 ·A 1 ), where said first node contends and transmits data packets T 0 times and of these A 0 are successful because an ACK is received by said first node; and where the first node transmits T 1 data packets after a Priority Interframe Spacing (PIFS) interval, which is shorter than a Distributed Inter-Frame Space (DIFS) interval, and of these A 1 are successful because an ACK is received by said first node.