Optimization of Cognitive Radio Secondary Information Gathering Station Positioning and Operating Channel Selection for IoT Sensor Networks

Table 1

Summary of notations.

Transmitting power	, ,	Transmitting power of SIGS, PUs, and SID
Set of primary or secondary systems		PBS set using channel j
		SIGS set using channel j
	{}	Set of unit cells that belongs to the SIGS
Channel gain		Channel gain between the PBS and the unit area (SID) using channel j
		Channel gain between the unit area and the SID using channel j
		Channel gain between the SIGS and the SID using channel j
		Channel gain between the SIGS and the SID using channel j
		Channel gain between the unit area and the PBS using channel j
		Channel gain between the PBS and the PBS using channel j
Number of unit areas		Number of unit areas covered by a SIGS
		Number of unit areas covered by a PBS
Coverage range		Coverage radius of the PBS
		Coverage radius of the SIGS
Appearance probability		SID appearance probability in the unit area
Noise		Noise density