Panoramic ship-borne sonar system - utilises single spectral analyser to process data from several receiver channels

摘要

The panoramic sonar system is for use on board a ship, it detects fixed or moving obstacles which are generally submerged, such as submarines. This is performed using a receiver in which several input channels are applied to a single spectral analyser. Sonar signals received on several channels (1) are applied to frequency changers (2) utilising a local oscillator (3). These signals are filtered (4) prior to sampling (7) and mixing (11). The mixer output is applied alternately to two memory circuits (16a, 16b) via a write switch (17). A read switch (18) applies these stored signals to an analyser (91) for display on a screen (93). A selector (94) allows the largest amplitude signals to be selected from a number of channels, in order to modulate the spot on the display tube.