Method to improve data obtained by a radar

US5861835A · kind A · utility

Inventor

• Hans Hellsten · Linköping, SE

Key dates

• Filing date: May 9, 1997
• Grant date: Jan 19, 1999
• Expiry date: May 9, 2017

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S13/90
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method of improving data obtained by radar by interpolation over frequency bands jammed by narrow-band interference, at which the following steps (A)-(J) are carried out. (A) It is determined what frequency values are affected by narrow-band interference. (B) Every radar return which is continuously connected in time and represented by a time-discrete real or complex signal f(t.sub.i), containing N sample, i=1, 2, . . . , N, is Fourier-transformed into a frequency-discrete function F(.omega..sub.i), given by N sample. (C) A series of integers N.sub.1, N.sub.2, . . . , N.sub.M is fixed, such that 1.ltoreq.N.sub.1 <N.sub.2 < . . . <N.sub.M <N. (D) The signal processing device sets F.sub.k (.omega..sub.i)=H.sub.k (.omega..sub.i) within intervals having narrow-band interference. (E) H.sub.1 (.omega..sub.i) is equated to 0 and H.sub.k (.omega..sub.i) for k.gtoreq.2 is constructed according to the following steps (F)-(H). (F) F.sub.k-1 (.omega..sub.i) is inversely Fourier-transformed into a time-discrete function f.sub.k-1 (t.sub.i). (G) The signal processing device sets h.sub.k (t.sub.i)=f.sub.k-1 (t.sub.i) for i=1, 2, . . . , N.sub.k-1, wherein .vertline.f.sub.k-1 (t.sub.i).vertline.…