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burnthru | BURN-THROUGH CROSSOVER RANGE The burn-through equations are derived in this section. These equations are most commonly used in jammer type of applications. The following is a summary of the important equations explored in this section J S CROSSOVER RANGE MONOSTATIC J S Rj s Pt Gt o Pj Gja 471 1 2 Ratio or 20 log Rt s 10logPt 10logGt 10log o -10logPj -10logGja - 10.99 dB Keep Pt Pj in same units Keep R and a in same units K1 Values dB Range f1 in MHz in GHz If simplified radar equations already converted to dB are used 20 log Rt s 10logPt 10logGt G - 10log Pj -10logGja -K1 -20log . f 1 in dB units K 1 m -27.55 ft -37.87 K 1 32.45 22.13 BURN-THROUGH RANGE MONOSTATIC The radar to target range where the target return signal S can first be detected through the ECM J . Rbt Pt Gt a J . eff Pj Gja 4n S 1 2 Ratio or 20logRBT 10logPt 10logGt 10logo -10logPj -10logGja 10log Jmin eff S - 10.99 dB Target gain factor dB G 10log o 20log f1 K2 K2 Values dB RCS 0 f1 in MHz in GHz units K 2 K 2 m2 -38.54 21.46 If simplified radar equations already converted to dB are used 20log Rbt 10logPt 10logGt Go -10logPj -10logGja - 10log Jmin efi S -20log f 1 in dB f 1 is MHz or GHz value of frequency ft2 -48.86 11.14 BURN-THROUGH RANGE BISTATIC Rtx istherangefromtheradartransmittertothetargetandisdifferentfromRRx which is the range from the target to the receiver. Use Monostatic equations and substitute RTx for R CROSSOVER RANGE and BURN-THROUGH RANGE To present the values of J and S or J S over a minimum to maximum radar to target range of interest equation 1 section 4-7. which has a slope of 20 log for J vs. range and equation 2 section 4-7 which has a slope of 40 log for S vs. range are plotted. When plotted on semi-log graph paper J and S or J S vs. range are straight lines as illustrated in Figure 1. Figure 1 is a sample graph - it cannot be used for data. The crossing of the J and S lines known as crossover gives the range where J S about 1.29 NM and shows that shorter ranges will .