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Chapter 14 pulls together many of the concepts by carrying out the beginning designs for several different applications. This appendix provides the programs that were used to obtain the calculations and the outputs of those programs.
The first example is the night-driving system. There are two programs for this, one for photon detectors and one for thermal detectors. The first program is for the photonic night driver. The standard format I like to use is to provide all the input values in the Setup subroutine. CLS and SCREEN clear the screen and set the monitor for SVGA in case I want to plot. For some reason this BASIC does not know the value of 7E. So I give it and the atomic constants that will get the first and second radiation constants for the Planck equation. Note that c, is in terms of c and h. A multiplier of 10 16 is necessary to get it in terms of centimeters and micrometers. Then I set the efficiencies and the transmissions. I use the last two lines alternately. If the last line is REMARKED, then the system works in the LWIR; if not, in the MWIR. I think the geometry and BANDWIDTH subroutines are clear. There are a lot of printing instructions to make sure things are the way they should be as the program proceeds. The SENSITIVITY subroutine uses the INTEGRATION subroutine that calculates all the blackbody functions. This same subroutine can be used for all the programs. Then there is a little optics calculation using the scheming equations.
The second program is for ambient-temperature, thermal detectors. The inputs are a little different. The specific detectivity is given and so are some of the properties of the optics. Only the one spectral band is used. Most everything else is the same.
The same scheme is used for ICBMs, but now the required values for out-of-field rejection and system temperature are determined from solar and terrestrial irradiances on the aperture. Then an iteration is used to get the temperature at which the system must be operated.
The PEACEKEEPER program uses a different method for calculating the bandwidth, since it is a strip-mapper, but it follows the textural prescription. Great similarities will be found in the other subroutines and this is no coincidence.
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