Simrad 9420024128749, Product Brief

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Halo™ - How Navico 3G/4G Works
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Navico Broadband Radar - Long Swept Frequency Modulated pulse
FMCW = Frequency Modulated Continuous Wave (a Frequency Diversity mode)
The transceiver transmits a ‘rising tone’ (Tx wave) with linear increasing frequency – at the same time the
signals are received – full duplex operation.
The wave propagates out at transmitter frequency. If it reflects off an object, it will return to the receiver,
still at the frequency it had when originally transmitted.
Meanwhile the transmitter continues to output an increasing frequency, the difference between the
currently transmitted and currently received frequencies, coupled with the known rate of frequency
increase, allows a time of flight to be calculated, from which we can calculate a distance.