Topographical mapping radar

In an airborne terrain contour mapping system, the combination of

• an aircraft,
• a radar antenna consisting of two vertically spaced fan beam antenna poles mounted on the aircraft,
• means to transmit thin, pencil-like radar signal at a depressed angle of between 20.degree. to 45.degree. from the antenna at directions normal to the flight path of the aircraft,
• means to measure and record the phase difference in the radar signals received at the two poles of the antenna when the signals are reflected from the earth,
• means to effect doppler sharpening to the returning radar signals,
• an inertial system to measure and record airborne platform orientation and position,
• means to combine the orientation and position information with the recorded radar information, and
• ground stationed means adapted to receive the combined information to provide a three coordinate output signal to effect a map of the contour of the terrain flown over by the aircraft.

In an airborne terrain contour mapping system, the combination of

• an aircraft,
• a radar antenna consisting of two vertically spaced fan beam antenna poles mounted on the aircraft,
• means to change the vertical separation between the poles of the antenna,
• means to pulse a radar signal from one pole of the antenna to scan the terrain beneath the aircraft,
• means to integrate the reflected signal returning to each pole of the antenna,
• means to effect doppler sharpening techniques to the integrated return signals,
• amplitude detection means adapted to receive the doppler sharpened integrated signals to provide depression angle information, and
• CRT display means modulated by the depression angle information to provide a high resolution radar strip map of the area scanned by the antenna.

In an airborne terrain contour mapping system, the combination of

• an aircraft,
• a dipole radar antenna consisting of two vertically spaced fan beam antenna poles mounted on the aircraft,
• means to change the vertical separation between the poles of the antenna,
• means to pulse a radar signal from one pole of the antenna to scan a section of the terrain beneath the aircraft,
• means to measure the phase difference of the reflected signal returning to each pole of the antenna,
• means to effect doppler sharpening techniques to the reflected return signals,
• amplitude detection means adapted to receive the doppler sharpened phase differentiated return signals to provide depression angle information, and
• CRT display means modulated by the depression angle information to provide a high resolution radar strip map of the area scanned by the antenna.

In an airborne terrain mapping system, the combination of

• an aircraft,
• a dipole radar antenna consisting of two vertically spaced fan beam antenna poles mounted on the aircraft,
• means to transmit radar signals at a depressed angle of between 20.degree. to 45.degree. from the antenna in a direction normal to the flight path of the aircraft,
• means to integrate the returning signals,
• means to effect doppler sharpening techniques to the returning signals,
• synchronous demodulator means to detect the phase difference between the reflected returning signals,
• CRT display and recording means modulated by the phase difference signals from the synchronous demodulator means to provide a high resolution radar strip map of the area scanned by the antenna,
• delay means to insure proper spacing between successive signals so that the contour lines displayed on the strip map will be sufficiently spaced for reading,
• means to change the phase relation of the returning signals to provide interpolation between signals,
• means to place a code base on the returning signals so the relation of the returning signals can be accurately determined,
• means to place a time base on the returning signals to insure proper linear resolving,
• inertial stabilization means to provide a smooth and stable flight path for the aircraft, and to provide datum information for the strip map,
• altitude indicting means to insure the proper altitude for the aircraft's flight path, and
• ground based resolving equipment adapted to utilize the strip map information which includes a line follower means to obtain three coordinate information from the strip map, means to print a contour map with the information from the line follower means, means to mill a raised relief map with the information from the line follower means, and means to make a photographic contour map utilizing the strip map and the informaton from the line follower means.

In an airborne terrain mapping system, the combination of

• an aircraft,
• a dipole radar antenna consisting of two vertically spaced fan beam antenna poles mounted on the aircraft,
• means to transmit radar signals at a depressed angle from the antenna in a direction normal to the flight path of the aircraft,
• means to effect doppler sharpening techniques to the returned signals,
• synchronous demodulator means to detect the phase difference between the reflected returning signals,
• CRT display and recording means modulated by the phase difference signals from the synchronous demodulator means to provide a high resolution radar strip map of the area scanned by the antenna,
• delay means to insure proper spacing between successive signals so that the contour lines displayed on the strip map will be sufficiently spaced for reading,
• means to change the phase relation of the returning signals to provide interpolation between signals,
• means to place a code base on the returning signals so the relation of the returning signals can be accurately determined,
• means to place a time base on the returning signals to insure proper linear resolving,
• inertial stabilization means to provide a smooth and stable flight path for the aircraft, and to provide datum information for the strip map,
• altitude indicating means to insure the proper altitude for the aircraft's flight path, and
• ground based resolving equipment adapted to utilize the strip map information which includes a line follower means to obtain three coordinate information from the strip map, means to print a contour map with the information from the line follower means, means to mill a raised relief map with the informaton from the line follower means, and means to make a photographic contour map utilizing the strip map and the information from the line follower means.

In an airborne terrain mapping system, the combination of

• an aircraft,
• a dipole radar antenna consisting of two vertically spaced fan beam antenna poles mounted on the aircraft,
• means to transmit radar signals at a depressed angle from the antenna in a direction normal to the flight path of the aircraft,
• means to effect doppler sharpening techniques to the returned signals,
• synchronous demodulator means to detect the phase difference between the reflected returning signals,
• CRT display and recording means modulated by the phase difference signals from the synchronous demodulator means to provide a high resolution radar strip map of the area scanned by the antenna,
• inertial stabilization means to provide a smooth and stable flight path for the aircraft and to provide datum information for the strip map,
• altitude indicating means to insure the proper altitude for the aircraft's flight path, and
• ground based resolving equipment adapted to utilize the strip map informaton to provide a raised relief map and a printed contour map.

In a terrain contour mapping system, the combination of

• an aircraft,
• an antenna system mounted on the aircraft,
• means to transmit radar signals at a depressed angle from the antenna in directions normal to the flight path of the aircraft,
• means to measure and record the terrain information received at the antenna from the reflected radar signals,
• an inertial stabilization system mounted on the aircraft to provide a stable platform for the antenna, and to record datum information, and
• ground based data processing equipment adapted to receive the recorded radar and datum informaton and to generate three coordinate information, and
• means adapted to receive the three coordinate information from the ground based processing equipment to provide a contoured relief map, and a raised relief map of the terrain flown over by the aircraft.

In a terrain contour mapping system, the combination of

• an aircraft,
• a dipole antenna system consisting of two vertically spaced fan beam antenna poles mounted on the aircraft,
• means to transmit radar signals at a depressed angle from one pole of the antenna in directions normal to the flight path of the aircraft,
• means to measure and record the phase difference of the returning terrain information received at the poles of the antenna from the reflected radar signals,
• an inertial stabilization system mounted on the aircraft to provide a stable platform for the antenna, and to record datum information,
• ground based data processing equipment adapted to receive the recorded radar and datum information and to generate three coordinate information, and
• means adapted to receive the three coordinate information from the ground based processing equipment to provide a contoured relief map, and a raised relief map of the terrain flown over by the aircraft.