itmlogic.preparatory_subroutines package¶

Submodules¶

itmlogic.preparatory_subroutines.dlthx module¶

itmlogic.preparatory_subroutines.dlthx.dlthx(pfl1, x1, x2)[source]¶

Use the terrain profile pfl1 to find delta h, interdecile range of elevations between point x1 and point x2, as described in Section 48 by Hufford (see references/itm.pdf).

Parameters:	pfl1 (list) – Terrain profile. x1 (int) – Point 1 x2 (int) – Point 2
Returns:	dlthx1 – Interdecile range of elevations
Return type:	float

itmlogic.preparatory_subroutines.hzns module¶

itmlogic.preparatory_subroutines.hzns.hzns(pfl, dist, hg, gme)[source]¶

Subroutine to find horizon parameters as described in Section 48 by Hufford (see references/itm.pdf).

Parameters:

pfl (List) – Terrain profile in meters.
dist (float) – Distance in meters.
hg (list) – Heights of transmitter and receiver off ground (meters).
gme (float) – Effective earth curvature.

Returns:

the (dict) – Horizon take-off angle.
dl (dict) – Horizon distances.

itmlogic.preparatory_subroutines.qlra module¶

itmlogic.preparatory_subroutines.qlra.qlra(kst, prop)[source]¶

Preparatory subroutine for area prediction mode, as described in equations (3.1)-(3.4) of “The ITS Irregular Terrain Model, version 1.2.2: The Algorithm” and as a function of the siting criteria for the transmit and receive terminals described using 2 element array KST (0=random, 1= “with care”, 2= “with great care”).

Parameters:	kst (list) – Siting criteria for the transmitter and receiver. prop (dict) – Contains all input propagation parameters.
Returns:	prop – Contains all input and output propagation parameters.
Return type:	dict

itmlogic.preparatory_subroutines.qlrpfl module¶

itmlogic.preparatory_subroutines.qlrpfl.qlrpfl(prop)[source]¶

Preparatory subroutine for point-to-point mode, as in Section 43 by Hufford (see references/itm.pdf).

Parameters:	prop (dict) – Contains all input propagation parameters.
Returns:	prop – Contains all input and output propagation parameters.
Return type:	dict

itmlogic.preparatory_subroutines.qlrps module¶

itmlogic.preparatory_subroutines.qlrps.qlrps(fmhz, zsys, en0, ipol, eps, sgm)[source]¶

General preparatory subroutine as in Section 41 by Hufford (see references/itm.pdf).

Parameters:	fmhz (int) – Carrier frequency. en0 – Surface refractivity reduced to sea level. zsysz – General system elevation. eps – Polarization. sgm – Ground constants. wn – Wave number ens – Surface refractivity. gme – Effective earth curvature. zgnd – Surface impedance.

itmlogic.preparatory_subroutines.zlsq1 module¶

itmlogic.preparatory_subroutines.zlsq1.avoid_zero_division(n, d)[source]¶

itmlogic.preparatory_subroutines.zlsq1.zlsq1(z, x1, x2)[source]¶

A linear least squares fit between x1 and x2, to the function described by the array z.

Evaluates a least squares fit to an input function z (in the form of a terrain profile having first element the number of profile samples, second element the spacing between them, and third through end elements the profile data) between horizontal locations x1 and x2. Returns the interpolated heights at location 0 and the end of the profile.