Plane earth model and MODIS landcover clutter

CHANGELOG

@@ -1,5 +1,8 @@
 SIGNAL SERVER CHANGELOG 
 
+2.9 - 01 September 2016
+MODIS Landcover support in ASCII Grid format. Works for 1200/3600 SRTM only.
+
 2.82 - 15 July 2016
 Fixed bug in SUI model which was making it over optimistic.
 

Makefile

@@ -8,7 +8,7 @@ LIBS		= -lm -lpthread
 
 VPATH		= models
 objects 	= main.o cost.o ecc33.o ericsson.o fspl.o hata.o itwom3.0.o \
-		  los.o sui.o inputs.o outputs.o
+		  los.o sui.o pel.o inputs.o outputs.o
 
 GCC_MAJOR	:= $(shell $(CXX) -dumpversion 2>&1 | cut -d . -f 1)
 GCC_MINOR	:= $(shell $(CXX) -dumpversion 2>&1 | cut -d . -f 2)
@@ -43,10 +43,10 @@ main.o: main.cc common.h inputs.hh outputs.hh itwom3.0.hh los.hh
 inputs.o: inputs.cc common.h main.hh
 
 outputs.o: outputs.cc common.h inputs.hh main.hh cost.hh ecc33.hh ericsson.hh \
-	   fspl.hh hata.hh itwom3.0.hh sui.hh
+	   fspl.hh hata.hh itwom3.0.hh sui.hh pel.hh
 
 los.o: los.cc common.h main.hh cost.hh ecc33.hh ericsson.hh fspl.hh hata.hh \
-       itwom3.0.hh sui.hh
+       itwom3.0.hh sui.hh pel.hh
 
 .PHONY: clean
 clean:

inputs.cc

@@ -6,6 +6,131 @@
 #include "common.h"
 #include "main.hh"
 
+int loadClutter(char *filename, double radius, struct site tx)
+{
+	/* This function reads a MODIS 17-class clutter file in ASCII Grid format.
+	   The nominal heights it applies to each value, eg. 5 (Mixed forest) = 15m are 
+	   taken from ITU-R P.452-11.
+	   It doesn't have it's own matrix, instead it boosts the DEM matrix like point clutter
+	   AddElevation(lat, lon, height);
+ 	   If tiles are standard 2880 x 3840 then cellsize is constant at 0.004166
+	 */
+	int x, y, z, clh, result, h, w;
+	double xll, yll, xur, yur, cellsize, cellsize2, xOffset, yOffset, lat, lon, i, j;
+	char line[50000];
+	char * pch;
+	FILE *fd;
+
+	fd = fopen(filename, "rb");
+
+	if (fd != NULL) {
+
+		if (fgets(line, 19, fd) != NULL) {
+			pch = strtok (line," ");
+			pch = strtok (NULL, " ");
+			w = atoi(pch);
+		}
+
+		if (fgets(line, 19, fd) != NULL) {
+			//pch = strtok (line," ");
+			//pch = strtok (NULL, " ");
+			h = atoi(pch);
+		}
+
+		if(w==2880 && h==3840){
+			cellsize=0.004167;
+			cellsize2 = cellsize * 2;
+		}else{
+			return 0; // can't work with this yet
+		}
+			if (debug) {
+				fprintf(stdout, "\nLoading clutter file \"%s\" %d x %d...\n", filename, w,h);
+				fflush(stdout);
+			}
+		if (fgets(line, 25, fd) != NULL) {
+			sscanf(pch, "%lf", &xll);
+		}
+
+		fgets(line, 25, fd);
+		if (fgets(line, 25, fd) != NULL) {
+			sscanf(pch, "%lf", &yll);
+		}
+
+		if (debug) {
+			fprintf(stdout, "\nxll %.2f yll %.2f\n", xll, yll);
+			fflush(stdout);
+		}
+
+		fgets(line, 25, fd); // cellsize
+
+		//loop over matrix
+		for (y = h; y > 0; y--) {
+				x = 0;
+				if (fgets(line, 100000, fd) != NULL) {
+					pch = strtok(line, " ");
+					while (pch != NULL && x < w) {
+						z = atoi(pch);
+						
+						// Apply ITU-R P.452-11
+						// Treat classes 0, 9, 10, 11, 15, 16 as water, (Water, savanna, grassland, wetland, snow, barren)
+						clh = 0;
+
+						// evergreen, evergreen, urban
+						if(z == 1 || z == 2 || z == 13)
+							clh = 20;
+						
+						// deciduous, deciduous, mixed
+						if(z==3 || z==4 || z==5)
+							clh = 15;
+						if(z==6)
+							clh = 4;
+						if(z==7 || z==12 || z==14)
+							clh = 2;
+
+						if(clh>1){
+							clh/=2; // Because heights are deliberately conservative
+							xOffset=x*cellsize; // 12 deg wide
+							yOffset=y*cellsize; // 16 deg high
+
+							// make all longitudes positive 
+							if(xll+xOffset>0){
+								lon=360-(xll+xOffset);
+							}else{
+								lon=(xll+xOffset)*-1;
+							}
+							lat = yll+yOffset;
+
+							// bounding box
+							if(lat > tx.lat - radius && lat < tx.lat + radius && lon > tx.lon - radius && lon < tx.lon + radius){
+								
+								// not in near field
+								if((lat > tx.lat+cellsize2 || lat < tx.lat-cellsize2) || (lon > tx.lon + cellsize2 || lon < tx.lon - cellsize2)){
+									AddElevation(lat,lon,clh);
+
+									// Create rectangle of dimensions cellsize x cellsize
+									for(i=cellsize*-1; i < cellsize; i=i+0.0005){
+										for(j=cellsize*-1; j < cellsize; j=j+0.0005){
+											AddElevation(lat+i,lon+j,clh);
+										}
+
+									}
+								}
+
+							}
+						}
+	
+						x++;
+						pch = strtok(NULL, " ");
+					}//while
+				} else {
+					fprintf(stdout, "Clutter error @ x %d y %d\n", x, y);
+				}//if
+			}//for
+	}
+	fclose(fd);
+	return 0;
+}
+
 void readLIDAR(FILE *fd, int hoffset, int voffset, int h, int w, int indx,
 	       double n, double e, double s, double west)
 {

inputs.hh

@@ -12,5 +12,6 @@ void LoadDBMColors(struct site xmtr);
 void LoadTopoData(int max_lon, int min_lon, int max_lat, int min_lat);
 void LoadUDT(char *filename);
 int loadLIDAR(char *filename);
+int loadClutter(char *filename, double radius, struct site tx);
 
 #endif /* _INPUTS_HH_ */

main.cc

@@ -1,4 +1,4 @@
-double version = 2.82;
+double version = 2.9;
 /****************************************************************************\
 *  Signal Server: Radio propagation simulator by Alex Farrant QCVS, 2E0TDW   *
 ******************************************************************************
@@ -33,6 +33,7 @@ double version = 2.82;
 #include "outputs.hh"
 #include "models/itwom3.0.hh"
 #include "models/los.hh"
+#include "models/pel.hh"
 
 int MAXPAGES = 64;
 int ARRAYSIZE = 76810;//76810;
@@ -1011,7 +1012,7 @@ int main(int argc, char *argv[])
 	unsigned char LRmap = 0, txsites = 0, topomap = 0, geo = 0, kml =
 	    0, area_mode = 0, max_txsites, ngs = 0;
 
-	char mapfile[255], udt_file[255], ano_filename[255], lidar_tiles[512];
+	char mapfile[255], udt_file[255], ano_filename[255], lidar_tiles[512], clutter_file[255];
 
 	double altitude = 0.0, altitudeLR = 0.0, tx_range = 0.0,
 	    rx_range = 0.0, deg_range = 0.0, deg_limit = 0.0, deg_range_lon;
@@ -1040,7 +1041,8 @@ int main(int argc, char *argv[])
 		fprintf(stdout, "Data:\n");
 		fprintf(stdout, "     -sdf Directory containing SRTM derived .sdf DEM tiles\n");
 		fprintf(stdout, "     -lid ASCII grid tile (LIDAR) with dimensions and resolution defined in header\n");
-		fprintf(stdout, "     -udt User defined CSV clutter file\n");
+		fprintf(stdout, "     -udt User defined point clutter as decimal co-ordinates: 'latitude,longitude,height'\n");
+		fprintf(stdout, "     -clt MODIS 17-class wide area clutter in ASCII grid format\n");
 		fprintf(stdout, "Input:\n");
 		fprintf(stdout,	"     -lat Tx Latitude (decimal degrees) -70/+70\n");
 		fprintf(stdout,	"     -lon Tx Longitude (decimal degrees) -180/+180\n");
@@ -1052,7 +1054,7 @@ int main(int argc, char *argv[])
 		fprintf(stdout,	"     -rxh Rx Height(s) (optional. Default=0.1)\n");
 		fprintf(stdout,	"     -rxg Rx gain dBi (optional for text report)\n");
 		fprintf(stdout,	"     -hp Horizontal Polarisation (default=vertical)\n");
-		fprintf(stdout, "     -gc Ground clutter (feet/meters)\n");
+		fprintf(stdout, "     -gc Random ground clutter (feet/meters)\n");
 		fprintf(stdout, "     -m Metric units of measurement\n");
 		fprintf(stdout, "     -te Terrain code 1-6 (optional)\n");
 		fprintf(stdout,	"     -terdic Terrain dielectric value 2-80 (optional)\n");
@@ -1065,7 +1067,7 @@ int main(int argc, char *argv[])
 		fprintf(stdout, "     -R Radius (miles/kilometers)\n");
 		fprintf(stdout,	"     -res Pixels per tile. 300/600/1200/3600 (Optional. LIDAR res is within the tile)\n");
 		fprintf(stdout,	"     -pm Propagation model. 1: ITM, 2: LOS, 3: Hata, 4: ECC33,\n");
-		fprintf(stdout,	"     	  5: SUI, 6: COST-Hata, 7: FSPL, 8: ITWOM, 9: Ericsson\n");
+		fprintf(stdout,	"     	  5: SUI, 6: COST-Hata, 7: FSPL, 8: ITWOM, 9: Ericsson, 10: Plane earth\n");
 		fprintf(stdout,	"     -pe Propagation model mode: 1=Urban,2=Suburban,3=Rural\n");
 		fprintf(stdout,	"     -ked Knife edge diffraction (Already on for ITM)\n");
 		fprintf(stdout, "Debugging:\n");
@@ -1082,8 +1084,8 @@ int main(int argc, char *argv[])
 
 	/*
 	 * If we're not called as signalserverLIDAR we can allocate various
-	 * memory now. For LIDAR stuff we need to wait until we've pasred
+	 * memory now. For LIDAR we need to wait until we've parsed
-	 * the headers in the .asc file to know how much memory to allocate.
+	 * the headers in the .asc file to know how much memory to allocate...
 	 */
 	if (!lidar)
 		do_allocs();
@@ -1096,6 +1098,7 @@ int main(int argc, char *argv[])
 	metric = 0;
 	string[0] = 0;
 	mapfile[0] = 0;
+	clutter_file[0] = 0;
 	clutter = 0.0;
 	forced_erp = -1.0;
 	forced_freq = 0.0;
@@ -1162,6 +1165,14 @@ int main(int argc, char *argv[])
 			}
 		}
 
+		if (strcmp(argv[x], "-clt") == 0) {
+			z = x + 1;
+
+			if (z <= y && argv[z][0] && argv[z][0] != '-') {
+				strncpy(clutter_file, argv[z], 253);
+			}
+		}
+
 		if (strcmp(argv[x], "-o") == 0) {
 			z = x + 1;
 
@@ -1606,7 +1617,9 @@ int main(int argc, char *argv[])
 		}
 	
 	}else{
+		// DEM first
 		LoadTopoData(max_lon, min_lon, max_lat, min_lat);
+
 			if (area_mode || topomap) {
 			for (z = 0; z < txsites && z < max_txsites; z++) {
 				/* "Ball park" estimates used to load any additional
@@ -1704,6 +1717,15 @@ int main(int argc, char *argv[])
 	// User defined clutter file
 	LoadUDT(udt_file);
 
+	// Enrich with Clutter
+	if(strlen(clutter_file) > 1){
+		/*
+		Clutter tiles cover 16 x 12 degs but we only need a fraction of that area.
+		Limit by max_range / miles per degree (at equator)
+		*/
+		loadClutter(clutter_file,max_range/45,tx_site[0]); 
+	}
+
 	if (ppa == 0) {
 		if (propmodel == 2) {
 			PlotLOSMap(tx_site[0], altitudeLR, ano_filename, use_threads);

models/README

@@ -5,3 +5,5 @@ Finding a reputable paper to source these models from took a while. There was
 lots of bad copy-paste out there. A good paper:
 
 http://www.cl.cam.ac.uk/research/dtg/lce-pub/public/vsa23/VTC05_Empirical.pdf
+
+Plane earth loss model taken from "Antennas and Propagation for Wireless systems" by Simon Saunders

models/los.cc

@@ -9,6 +9,7 @@
 #include "hata.hh"
 #include "itwom3.0.hh"
 #include "sui.hh"
+#include "pel.hh"
 #include <pthread.h>
 
 #define NUM_SECTIONS 4
@@ -467,7 +468,7 @@ void PlotPropPath(struct site source, struct site destination,
 						  METERS_PER_FOOT), dkm, pmenv);
 				break;
 			case 4:
-				// COST231-HATA
+				// ECC33
 				loss =
 				    ECC33pathLoss(LR.frq_mhz, txelev,
 						  path.elevation[y] +
@@ -484,6 +485,7 @@ void PlotPropPath(struct site source, struct site destination,
 						 METERS_PER_FOOT), dkm, pmenv);
 				break;
 			case 6:
+				// COST231-Hata
 				loss =
 				    COST231pathLoss(LR.frq_mhz, txelev,
 						    path.elevation[y] +
@@ -517,6 +519,11 @@ void PlotPropPath(struct site source, struct site destination,
 						     pmenv);
 				break;
 
+			case 10:
+				// Plane earth
+				loss =	PlaneEarthLoss(dkm, txelev, path.elevation[y] + (destination.alt * METERS_PER_FOOT));
+				break;
+
 			default:
 				point_to_point_ITM(source.alt * METERS_PER_FOOT,
 						   destination.alt *
@@ -529,7 +536,7 @@ void PlotPropPath(struct site source, struct site destination,
 						   loss, strmode, errnum);
 
 			}
-			
+
 			if (knifeedge == 1) {
 				diffloss =
 				    ked(LR.frq_mhz,

models/pel.cc

@@ -0,0 +1,29 @@
+/*****************************************************************************
+*  Plane Earth Path Loss model for Signal Server by Alex Farrant             *
+*  Taken from "Antennas and Propagation for wireless communication systems"  *
+*  ISBN 978-0-470-84879-1                                                    *
+*  10 August 2016							     *
+*  This program is free software; you can redistribute it and/or modify it   *
+*  under the terms of the GNU General Public License as published by the     *
+*  Free Software Foundation; either version 2 of the License or any later    *
+*  version.								     *
+*									     *
+*  This program is distributed in the hope that it will useful, but WITHOUT  *
+*  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or     *
+*  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License     *
+*  for more details.							     *
+*									     */
+
+#include <math.h>
+
+double PlaneEarthLoss(float d, float TxH, float RxH)
+{
+/*
+Plane Earth Loss model 
+Frequency: N/A
+Distance (km): Any
+*/
+	// Plane earth loss is independent of frequency.
+	double dbloss = 40*log10(d) + 20*log10(TxH) + 20*log10(RxH);
+	return dbloss;
+}

models/pel.hh

@@ -0,0 +1,6 @@
+#ifndef _PEL_HH_
+#define _PEL_HH_
+
+double PlaneEarthLoss(float d, float TxH, float RxH);
+
+#endif /* _PEL_HH_ */

signalserverHD

@@ -0,0 +1 @@
+signalserver

signalserverLIDAR

@@ -0,0 +1 @@
+signalserver