METHOD FOR SINGLE-BEAM DETERMINATION OF THE ALTITUDE AND SPEED PARAMETERS OF AN AIRCRAFT BASED ON THE SIGNALS OF A COHERENT RADIO ALTIMETER Russian patent published in 2022 - IPC G01S13/42 G01S13/58 G01S13/60 

FIELD: radio navigation.

SUBSTANCE: invention relates to radio navigation and can be used to measure the height and speed components of an aircraft in radio altimeters (RA) of aircraft, including in RA of unmanned aerial vehicles. In the claimed method, the stages of vertical probing of the Earth’s surface, coherent single-beam reception of the reflected signal, finding the maximum contrast curve n_R (k_F) on the range-Doppler portrait (RDP) by two independent methods for the range n_R and frequency k_F, summing them to obtain the resulting maximum contrast curve n_RΣ(k_F); incoherent summation of the maximum contrast curves of several RDPs and morphological processing of the resulting maximum contrast curve with the rejection of false counts, finding the optimal current estimate of the state vector X_i =(H_i, V_Πi, V_Bi)^T, i is the index of the hypothesis about the current H_i: height, V_Πi is the ground speed and V_Bi is the vertical speed of the aircraft. The optimal estimation of the state vector X_i is found through nonlinear filtering of the discrepancy of the predicted hypothesis about the range of the aircraft to the maximum contrast curve R_i(k_F, X_i) relative to the range of the aircraft to the resulting maximum contrast curve of the observed RDP n_RΣ(k_F). When n_RΣ(k_F) is found, the maximum contrast curve readings obtained when finding the position of the reflected signal power jump in the range from to where is the minimum range to the resolvable elements of the RDP, the power of the reflected signal from which exceeds the detection threshold, δ_R is the resolution of the probing signal for the range.

EFFECT: increase the accuracy and stability of single-beam measurement of altitude, track and vertical speed of aircraft over various types of surfaces.

1 cl, 1 ex, 4 dwg