{"id":5374,"date":"2019-01-12T13:47:50","date_gmt":"2019-01-12T18:47:50","guid":{"rendered":"https:\/\/dronebotworkshop.com\/?p=5374"},"modified":"2023-04-12T11:53:54","modified_gmt":"2023-04-12T15:53:54","slug":"rcwl-0516-experiments","status":"publish","type":"post","link":"https:\/\/dronebotworkshop.com\/rcwl-0516-experiments\/","title":{"rendered":"Experiments with the RCWL-0516 – Doppler Radar Distance Sensor"},"content":{"rendered":"\n

\"Download \"Parts<\/a> \"View<\/a> \"Download<\/a><\/p>\n

Introduction<\/span><\/h2>\n

Proximity sensing is a common application for intruder alarms, light switches, and other home and industrial automation applications. \u00a0And there are several ways of accomplishing it.<\/span><\/p>\n

We have already looked at using a <\/span>PIR Sensor<\/span><\/a>, this device senses the change in ambient infrared energy caused when a warm body (human or animal) enters the monitored area.<\/span><\/p>\n

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Another method of proximity detection involves using reflected <\/span>ultrasonic<\/span><\/a> or <\/span>light beams<\/span><\/a>, the intruding object reflects the beams back to their source where the time delay between transmission and reception is measured to calculate the distance to the object.<\/span><\/p>\n

Today we will look at another method of proximity detection, this time using microwaves and a scientific phenomenon called the \u201cDoppler Effect\u201d. As advanced as this sounds it can be accomplished both easily and inexpensively using a unique little sensor, the RCWL-0516.<\/span><\/p>\n

The RCWL-0516<\/span><\/h2>\n

The RCWL-0516 is a small proximity sensor that uses Dopler Radar to sense the presence of an intruder. It is very versatile and can be used on its own or in conjunction with a microcontroller or microcomputer.<\/span><\/p>\n

\"RCWL-0516<\/p>\n

This device does not consume much current and operates in a range of 4 to 28 volts, making it an ideal component for a battery-powered design.<\/span><\/p>\n

The microwave antennas are integrated onto the small printed circuit board, making it a completely self-contained unit.<\/span><\/p>\n

The RCWL-0516 also support an optional light-dependent resistor (LDR) to allow the device to operate only in darkness. This can be very useful in light control applications.<\/span><\/p>\n

Module Description <\/span><\/h3>\n

The module is a single circuit board with the following connections:<\/span><\/p>\n

\"RCWL-0516<\/p>\n

Be certain that you note that the <\/span>3V3<\/span><\/i> pin is a 3.3-volt output, not a power supply input. The device has an integrated 3.3 volt voltage regulator which can provide up to 100 mA of current for powering external logic circuitry.<\/span><\/p>\n

The <\/span>Output<\/span><\/i> pin is a 3.3-volt logic level pin. When the device detects a moving object it will send this pin HIGH for two seconds. \u00a0The device does not measure the distance to the detected object or its velocity, just its presence.<\/span><\/p>\n

The <\/span>VIN<\/span><\/i> pin is the positive power supply input, accepting any voltage from 4-volts to 28-volts. The RCWL-0516 does not consume very much current and can easily be powered by the 5-volt output from an Arduino or a Raspberry Pi.<\/span><\/p>\n

The <\/span>CDS<\/span><\/i> pins are where you can attach an optional light sensor, a light dependent resistor (LDR). \u00a0The LDR can actually be hooked up two ways:<\/span><\/p>\n