About ECM: SSJ & SOJ
Note: this app is probably too large for phones but OK for tablets and PCs. For a tracking radar, enter the power in kW antenna gain in dB, and IF bandwidth in MHz. Then enter the aircraft cross sectional area in m^2 and the range in km, for a self-screening jammer on board with transmitter power in kW over a bandwidth in MHz and given antenna gain in dB at a distance from the radar in km These values are for the J/S (SSJ) in dB,
Next, for the same jammer in a stand-off scenario and a sidelobe in dB level for the radar antenna, enter Rj and SL values to find J/S (SOJ).
For example, Enter Pt = 100, Gr = 35, Br = 1, A = 4, R = 3, Pj = 1, Bj = 20, Gj = 10, Rj = 10, & SL = 20. Your values for J/S (SSJ) and J/S (SOJ) should be 16.5 & -14.0 dB, respectively.