Radio navigation distance measurement radio wave refraction error correction method

Abstract

The invention provides a radio navigation distance measurement radio wave refraction error correction method. A mathematical model of the apparent elevation angle, the flight height and the apparent distance between an aircraft and a ground beacon is constructed, the geocentric field angle of the aircraft apparent elevation angle and the ground beacon at different heights is calculated, the real elevation angle between the aircraft and the ground beacon is calculated, the real distance between the aircraft and the ground beacon is calculated, and the atmospheric refraction distance measurementerror is calculated. The method is based on the atmospheric refraction theory and radio navigation equipment application, the mathematical model of the radio navigation atmospheric refraction distance measurement error, the flight height of the aircraft and the apparent distance of the ground beacon is constructed, a distance correction algorithm is provides, and the method has practicability anduniversality for radio navigation distance atmosphere refraction error correction, can obviously improve the radio navigation distance measurement precision, and fills up the blank in the field of radio navigation atmosphere refraction error correction. The method also has a certain reference value for distance measurement based on radio pulses.

Description

technical field [0001] The invention belongs to radio navigation and is used for correcting radio navigation distance measurement errors caused by electric wave refraction. Background technique [0002] The distance measurement of radio navigation is based on the principle of secondary radar, including ground beacons and airborne equipment (such as figure 1 As shown), the airborne equipment sends out a ranging query pulse. After receiving the ground beacon, it transmits a response signal after a fixed delay. The airborne equipment demodulates and decodes the response signal to measure the time between the query pulse and the response signal. The distance between the aircraft and the ground beacon can be calculated by subtracting the fixed time delay of the ground beacon from this time value. The calculation formula is as follows: [0003] [0004] Among them: R is the distance between the aircraft and the ground beacon measured by the airborne equipment; T is the time in...

AI Technical Summary

Problems solved by technology

[0005] A radio wave in a vacuum is 3×10 8 The speed of m / s propagates along a straight line, but due to the influence of atmospheric inhomogeneity, the refractive index of the atmosphere will change, resulting in the refraction effect of radio waves, and the propagation rays will be bent, making the propagation speed smaller than the speed in vacuum, resulting in radio navigation airborne equipment The measured distance is greater than the actual distance between the aircraft and the ground equipment

[0006] At present, due to the lack of a perfect correction method for the distance measurement error of radio navigation wave refraction, the correction of this deviation is ignored

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