Table 1: Definitions of the main symbols used throughout the paper.

Symbol Description

Data gathering delay: time available for a mobile BS tour
Transmission range of a sensor node
Maximum allowable length of the mobile BS tour,
Actual length of the mobile BS tour
Length of the mobile BS tour connecting cluster centroids
, Average and maximum speed of the mobile BS, respectively
Packets request time, from data request to receiving the first data packet
Packet time: average time required to transmit a data packet to the BS
Contact time
Residual contact time
Total time to send data of the cluster nodes to the BS ( )
Radius of the network field
Network nodes
Number of the clusters
Number of nodes in a cluster
Number of nodes the cluster head can successfully send their data to the BS
Number of packet losses