TABLE OF CONTENTS The radar s transmitted power is a basic quantity that defines its range performance. Unfortunately, transmit power is difficult to estimate from the ELINT point of view. Historically, transmitter power was one of the last aspects of a signal to be examined by signal analysis. In ELINT work, the quantity that can be most readily estimated is the peak effective radiated power (ERP), which is the product of the peak transmit power, the antenna gain, and any loss between the transmitter and transmit antenna. (The radar s antenna gain can be estimated from its beam pattern, and then the peak transmit power can also be estimated once the ERP is determined.) Consider the one-way or ELINT range equation. Solving this equation for the ERP gives the following result:
where:
P T = transmitted power
G TE = transmit antenna gain in the direction of the ELINT site
L T = losses at the transmitter
S E = received signal power
R E = distance from the transmitter to the ELINT site
L E = losses at the ELINT receiver
G E = gain of the ELINT site antenna in the direction of the transmitter
? = wavelength = speed of light divided by the RF
In radar usage, the term peak power means the transmitted power averaged over the duration of one pulse. The term average power means the power averaged over one PRI. The average power is related...
