Radar Detection - MATLAB Simulations for Radar Systems Design - page 111

which is identical to Eq. (2.106) when K 1 = K 0 and n P = 1 .

2.10. ÐMyRadarÑ Design Case Study - Visit 2 1

2.10.1. Problem Statement
Modify the design introduced in Chapter 1 for the ÐMyRadarÑ design case
study so that the effects of target RCS fluctuations are taken into account. For
this purpose modify the design such that: The aircraft and missile target types
follow Swerling I and Swerling III fluctuations, respectively. Also assume that
a is required at maximum range with or better. You
may use either non-coherent integration or cumulative probability of detection.
Also, modify any other design parameters if needed.

– 7

P D ≥ 0.995 P fa = 10

2.10.2. A Design

The missile and the aircraft detection ranges were calculated in Chapter 1.
They are for the aircraft and for the missile. First,
determine the probability of detection for each target type with and without the
7-pulse non-coherent integration. For this purpose, use MATLAB program
Ðmyradar_visit2_1.mÑ given in Listing 2.27. This program first computes the
improvement factor and the associated integration loss. Second it calculates the
single pulse SNR. Finally it calculates the SNR when non-coherent integration
is utilized. Executing this program yields:

R a = 90 Km R m = 55 Km

SNR_single_pulse_missile = 5.5998 dB
SNR_7_pulse_NCI_missile = 11.7216 dB
SNR_single_pulse_aircraft = 6.0755 dB
SNR_7_pulse_NCI_aircrfat = 12.1973 dB

Using these values in functions Ðpd_swerling1.mÑ and Ðpd_swerling3.mÑ
yields

Pd_single_pulse_missile = 0.013
Pd_7_pulse_NCI_missile= 0.9276
Pd_single_pulse_aircraft = 0.038
Pd_7_pulse_NCI_aircraft = 0.8273

Clearly in all four cases, there is not enough SNR to meet the design require-
ment of P D ≥ 0.995 .

1. Please read disclaimer in Section 1.9.1.