METHOD AND X-RAY ALTIMETER FOR MEASURING LOW ALTITUDES Russian patent published in 2004 - IPC

FIELD: radiation instrumentation engineering; altitude meters for flying vehicles.

SUBSTANCE: proposed method intended for controlling pulse-operated X-ray instruments on board flying vehicles of various types during their final approach or in flight at low altitudes includes irradiation of reflector surface by X-ray pulses at fixed frequency and duration, and recording or backward dissipated radiation. Entire range of altitudes being measured is covered by equal-length strobes, the latter are locked to time axis, and quantity of pulses N₁, N₂, …, N_k recorded within accumulation time step are recorded in each strobe. Threshold values are found in advance and compared with number of pulses in each strobe with respective threshold value. Strobe number m incorporating signal maximum is detected by maximal increase. G_m functional is calculated from formula: G_m = (N_{m + 1} - N_m)/(N_{m + 1} + N_m), where N_m and N_{m + 1} is quantity of accumulated pulses in strobes bearing ordinal numbers m and m + 1, respectively; then altitude is found, that is, point is found on pre-constructed calibration curve g_m that corresponds to G_m functional (Y coordinate), and its X-coordinate will show target value of altitude; X-ray altimeter implementing proposed method has X-ray transmitter, detecting unit, strobe shaper, multitapped delay line, k coincidence circuits, k counters, and computer, all interconnected in definite way. Altimeter may be provided in addition with controlled master oscillator connected to altimeter and X-ray transmitter.

EFFECT: enhanced precision and reliability of system for real-time analysis of time division of inversely dissipated rays throughout entire measurement range.

2 cl, 5 dwg