Table 1 Notations and meanings

S

Length of space for each vehicle

L _i

Transmission range of an AP when the specific transmission rate r _i is used

q

Vehicle arrival rate that counts the number of vehicles passing a fixed roadside observation point per unit time

v

Vehicle speed

k

Vehicle density

v _f

Speed when the vehicle is alone on the road

k _jam

Traffic jam density when traffic flow comes to a halt

λ

Mean vehicle arrival rate

T _i

Sojourn time in the coverage of 2L _i

p _N

Steady state probability with N vehicles in the coverage of an AP

C _i

Maximum number of vehicles in the coverage of an AP

I

Elapsed time since the light turned red

M

Number of remaining vehicles after the last green light signal

E

Number of outgoing vehicles during the green light signal

T(N)

Overall transmission time of a single node when N nodes exist

t _tr

MAC protocol data unit (MPDU) transmission time

t _ack

MAC acknowledgement transmission time

t _pr

Physical layer convergence protocol (PLCP) preamble and header transmission time

t _ov

Constant overhead that includes DIFS = 50 μ s, SIFS = 10 μ s, t_ack , and t_pr

t_cont(N)

Channel contention time when N nodes exist

G _i

Group of nodes with the i th highest transmission rate r _i

N _i

Number of nodes included in G _i

$t_{\mathsf{\text{ov}}}^{r_i}$

Constant overhead time of a node in G _i

T _i

Overall transmission time of a node in G _i

T_jam(N)

Average time spent by collisions when N nodes exist

b

Number of groups

P _C (N)

Conditional collision probability when N nodes exist

CW _min

Minimum contention widow size

X _l

Expected throughput of a super group (1, ...,l)

SNR _i

SNR threshold to be a member of G _i