K-HC1 RADAR TRANSCEIVER

Datasheet

Application Notes

Sensitivity and Maximum Range

The values indicated here are intended to give you a 'feeling' of the attainable detection range with this

module. It is not possible to define an exact RCS (radar cross section) value of real objects because

reflectivity depends on many parameters. The RCS variations however influence the maximum range

Maximum range for Doppler movement depends mainly on:

- Module sensitivity (for S/N ration > 6dB)

S:

-164dBc (@1kHz IF bandwidth)

- Carrier frequency

24.125GHz

- Radar cross section RCS ("reflectivity") of the object

The famous "Radar Equation" may be reduced for our K-band module to the following relation:

4

40

10

0167

.

0









s

r

Using this formula and a comparator as ADC, you get an indicative detection range of

- > 210 meters for a moving person

- > 560 meters for a moving car

Please note, that range values also highly depend on the performance of signal processing,

environment conditions (i.e. rain, fog), housing of the module and other factors.

Maximal distance is also limited by the phase noise of the oscillator. With K-HC1, you get an absolute

maximum range of > 1km.

High Sensitivity Sensor

The superhet architecture leads to a significantly better signal to noise (S/N) ratio than the direct

conversion principle used in traditional Doppler transceivers.

K-HC1 features an enhancement of 20-25dB compared to a K-MC1 sensor. This means a 4 times

distance enhancement. (Each 12dB means doubling the distance range).

Typical applications are

•

Long range movement detection of persons up to 400m

•

Speed measurements in sports applications (persons, balls, …)

•

Long range traffic detector (cars up to 1'000m)

Best results regarding maximum distance may be achieved by using FFT processing.

© RFbeam Microwave GmbH, Schuppisstrasse 7, CH-9016 St. Gallen

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