Notation Meaning	Notation Meaning
CH	Cluster Head
CM	Cluster Member
BS	Base Station
n	Total number of wireless sensor nodes
l	Length of message in Bits
p	Probability to select a node as CH
T(sni)	Threshold function value against ith sensor node
DT	Direct Transmission
TDMA	Time Division Multiple Access
	Remaining energy level of the node during the ith round
	Energy will be consumed by the elected CH during the ith round
E0	Initial assigned energy level
M	Network diameter
m	Number of clusters
K	Optimal number of CHs
	Transmitter amplifier refers to the free space mode
	Transmitter amplifier refers to the multi-path attenuation mode
Eprocessing	Energy consumption in local processing
ETx	Transmitter Electronics
ERx	Receiver Electronics
Eelec	Energy consumption of transmitting l-bit
	Critical value for dividing the spatial model.
DRN	Death Rate of Nodes
FND	First Node Died
HND	Half of the Nodes Died
SRE	System Residual Energy

Table 1: Summary of the used notations

Parameters	Value
Sensing Area	100 × 100 m2,
Node Density (n)	100
Initial Energy of each node (E0)	0.25J, 0.5J, 1.0J
Energy dissipation: receiving (Eamp)	0.0013 pJ/bit/m4
Energy dissipation: free space model (Efs)	10 pJ/bit/m2
Energy dissipation: power amplifier (Eamp)	100 pJ/bit/m2
Energy dissipation: aggregation (EDA)	5 nJ/bit
Data Packet Length (Bits)	2000, 4000