Mixer Pulse Blanking Unit (MPBU) – 1992
Any ship of the Royal Netherlands Navy has multiple transmitters and receivers on board for radar, Electronic Warfare (EW), and communication. A transmitter may cause interference in the other receivers. The disturbance can be of such a nature that those receivers emit undesired signals during the transmitted pulse and some time thereafter. Disturbances caused by one’s transmitters can be suppressed. The Mixer Pulse Blanking Unit (MPBU) was designed for that purpose. The MPBU ensures that when transmission occurs, all receivers that could be disturbed by the transmitter receive a special signal (“blanking”) that prevents the receiver from sending unwanted signals. Of course, the “blanking” time will have to be as short as possible to maximise the effective listening time of the receivers.
For each of the ship’s transmitters measurements are made to determine which receivers are disturbed by the transmitter and during which period. That period can be longer than the disturbing transmit pulse. Based on these measurements, a matrix can be built with states about when and for how long to ‘exclude’ a broadcast. All this data is stored in the memory of the MPBU.
For any transmitter that becomes active thereafter, the necessary blanking pulses are generated and sent to the relevant receivers. The blanking status is also presented – whether or not blanking is active – of the receivers both on the device itself and on a separate status panel. The latter is the so-called Command Authorization Panel (CAP).
The MPBU has been installed on a large number of the Royal Netherlands Navy ships.