#130 A Few DIY Radar Sensors
One sensor that’s been incredibly useful to me is the radar sensor. Over the past few years I’ve made quite a few different versions with great results and many improvements especially in power consumption. One of the most useful features is the ability to place wood or plastic over the entire sensor effectively covering the entire unit from sight. This allows the device to be placed covertly in very effective positions. The biggest issue is ensuring the alarm signal can be transmitted from these locations and that’s where LoRa technology comes into play.
RF 2.4GHZ and 433MHz,Wifi and LoRa are some of the most well known and common low bandwidth digital wireless communication methods, of course we could use a classic analogue radio to send digital square wave signals like the very early alarm systems but that tends to make the device a power hog and increases the size of the device however more power can also have great pros like increasing the transmission and, having less interference affecting the signal and even some level of immunity to jammers.
However I always focus on low power and low current applications I want my sensors to do the job in remote areas with solar power or hefty batteries running them for years without breaking the bank.
During my journey I started with basic breadboard projects moved to more permanent perfboard and strip board projects and eventually started creating fully fledged PCBs for these devices. I encountered various problems like matching antennas to increase the transmission effectiveness, waterproofing and powering the devices with solar and batteries, the effect the blazing hot African sun has on enclosures outside for years, consuming the least amount of current and running the microcontrollers in the most effective configuration suited to their purpose and I can go on.. there’s always something new to learn and I bet there will be even more advancements in Radar technology assuming solar flares or nuclear war or maybe even aliens don’t destroy our electronic and electrical technologies. we have our ancestors to thank for creating and sharing this power with us over the many many decades and hopefully we will eventually evolve to colonize the stars… well ahem I guess that’s a bit ironic coming from a South African but ideas are stronger than any country government or religion I can only hope we keep moving forward.
