Hi Frank, Antennas are characterized by either antenna factors or antenna gain. Antenna factors are used for the reason of simplicity. Antenna gain is an indicator of how much specific antenna is more efficient from the isotropic radiator. To get actual field strength level we will need antenna gain and isotropic antenna factor at each frequency if antenna gain is used instead of antenna factor. Antenna factor one value per frequency is being used instead of two (antenna gain and isotropic antenna factor).
Mirko Matejic ---------- From: F.Goto To: [email protected] Subject: Antenna gain vs. factor List-Post: [email protected] Date: Thursday, August 06, 1998 7:32PM Hi All, I have another question from our EMC department. Help from anyone knowledgeable in the area would be appreciated. I would like to know about NSA Measurement(Normalized Site Attenuation). The expression on ANSI 63.4 and CISPR 16 states, A=V(Direct)-V(Site)-AF(T)-AF(R)-AF(TOT) Where A :Normalized Site Attenuation V(Direct):is direct connection from one antenna to another antenna. V(Site) :is maximum signal measured with the receive antenna scanned in hight AF(T) :Antenna factor of transmitting antenna AF(R) :Antenna factor of Receiving antenna AF(TOT) :Mutual impedance correction factor Why do we use AT(T) instead of Antenna gain? Sincerely, Frank F. Goto A-pex International Co., Ltd. 1st Engineering Department 248-1 Kusube-cho Ise-shi, Mie-ke 516-0014 Japan Tel: +81-596-24-6717 Fax:+81-596-27-5631 [email protected] http://a-pex.co.jp --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], or [email protected] (the list administrators).
