MONOSTATIC INTERFEROMETRIC DIGITAL RADAR WITH PULSE COMPRESSION AND SYNTHETIC APERTURE IN-SAR, APPLICABLE IN MONITORING SUBMILLIMETER MASSIVE STRUCTURE DISPLACEMENTS AND LANDSLIPS

摘要

The invention relates to a monostatic interferometric digital radar with pulse compression and synthetic aperture, applicable in remote monitoring of massive structure displacements and landslips. According to the invention, the radar comprises a digital unit (A) controlled by a computer (1) which controls the operation of a radar by means of a USB interface (6) and an Ethernet interface (7), where the USB interface (6) is connected to another interface (4) by which switch-on signals are generated for a linear variable voltage generator (5) and by which a unit (C) for mechanical displacement of the radar is controlled, while the Ethernet interface (7) is connected to an acquisition system (2) to which a high speed analogue-to-digital converter (3) is connected to digitalize, on two channels (8 and 9), the analogue signals received from the analogue unit (B) which comprises, on the emission channel, the following components: a voltage-controlled oscillator (11), a band-pass filter (12), a directional coupler (13), an amplifier (14), an emission antenna (22), a splitter (15) and a mixer (16), and, on the receiving channel, a receiving antenna (23), a receiving amplifier (21) and a mixer (20), the two channels having common local oscillator (17), separation amplifier (18) and splitter (19). This way, focused radar images are obtained, presented as colour-coded distance-azimuth maps, where the colour is a function which depends on the transverse radar section of targets in the field. After successive scanning operations performed on the same scene, the analysis of the evolution of signal phase from one scanning operation to the next one results in radar interferograms which point out the short-, medium- or long-term changes of relative distance between the radar and the scene components.