From: Evaluation of a duty-cycled asynchronous X-MAC protocol for vehicular sensor networks
Symbol | Quantity |
---|---|
N | Number of nodes in the network |
T | Length of a cycle |
W | Contention window size in units of a time slot |
M | Queue capacity in units of a data packet |
m | Number of data packet in queue |
S | Data packet size |
ı,ȷ | the state of node |
P _{ ı,ȷ } | the probability of transition from state ı to state ȷ for the node |
p _{ f } | Probability of transmission failure of data packet |
p _{ s } | Probability of successfully transmission of data packet |
n | Number of sensor nodes in specified area |
ρ | Density of sensor nodes |
T _{ r } | Transmission range |
T _{ s } | Sensing range |
T _{ I } | Interference range |
λ | Expected data packet arrival rate at the MAC layer |
A _{ ı } | Probability of ı data packets arriving in a cycle |
π | The stationary distribution of the Markov model |
τ | The probability of an arbitrary node transmitting in time slot |
D | Packet delay |