Hi..
I want to transmit a pulse for every one second and measure the reflected signal. Set a threshold on the reflected signal and alert if the reflected signal level is low.
What is the best wireless technology I can go with?
Can BLE beacon do the job for me?
Or if am using the xbee, can I continuously send a pulse and detect the reflected pulse ?
Basically I want to detect some obstacles like a radar at the same time send message to the gateways over wifi or ble or xbee if something is detected...

Major construction is a power..
Should be < 20 uA in sleep mode where the pulses are transmitted continuously..
And can be 50-60 mA while sending the detection info though the gateway...

 

Assuming you are talking about an RF physically reflected pulse? Or the response of another remote device?
Your question lacks detail.

Light and radio signals travel 300,000,000 meters per second, what you are talking about doing is very difficult.
None of the available RF communication modules are going to give you any time-of-flight information.

 

Assuming you are talking about an RF physically reflected pulse? Or the response of another remote device?
Your question lacks detail.

Light and radio signals travel 300,000,000 meters per second, what you are talking about doing is very difficult.
None of the available RF communication modules are going to give you any time-of-flight information.

Well... Let me give u an example...
Consider the radar signal... It transmits a pulse(or series of pulse) and analyse the reflected pulse either for distance calculaton or for signal attenuation.
Similarly, consoconan ultrasonic distance sensor where an ultrasonic sensor emmits a ultrasiult pulse and analyse the reflected echo...
So is there any chip that does the same job using either 2.4 GHz or 830/434MHz band...?
If so, I can detect any object and at the same I can build any xbee/WiFi/lora network too for data transmission as well rather using the seperate communication networks..

 

Why are you insisting that it be radio frequency? There are plenty of TOF photonic chips available (just search on "TOF chips").

EDIT: Here's a "motion detector" that works at 10.5 GHz: https://www.parallax.com/product/32213

 

How about sonar? Lots of ways to do that.
The Cypress hybrid uCs have an app note for a 1 chip build.
I built one to just play with, its an elegant answer. <<<)))

 

What objects are you trying to detect and at what distance?

 

Why are you insisting that it be radio frequency? There are plenty of TOF photonic chips available (just search on "TOF chips").

EDIT: Here's a "motion detector" that works at 10.5 GHz: https://www.parallax.com/product/32213

Why are you insisting that it be radio frequency? There are plenty of TOF photonic chips available (just search on "TOF chips").

EDIT: Here's a "motion detector" that works at 10.5 GHz: https://www.parallax.com/product/32213

Hi..
Thanks for your reply..
And this is interesting..
Basically I want to detect the presence of any vehicle... As soon as I detect, I want to send that info to my gateway.. Currently am using xbee as a communication protocol and magnetic sensor for sensing vehicles...
But xbee is not reliable when my sensor is underneath the vehicle and magnetic sensors are also not up to the mark .. Again thsetwork on battery and should last for atleast 5 years... Hence am worrying about extremely low power/ current sensors and communication networks..
I thought if the beacon is going to send some info to its controller, I can measure it's signal strength and use it for decifidethe presence of a vehicle

 

How about sonar? Lots of ways to do that.
The Cypress hybrid uCs have an app note for a 1 chip build.
I built one to just play with, its an elegant answer. <<<)))

Sonar doesn't work for me..
It has to pass through my encloser, consume very less power, should be a water proof and finally detect vehicles accurately when burried on the road..

 

I do not have a lot of experience with RF links. I have, rather simplistically, turned to XBee when I wanted one, but I am sure equally capable links at less cost are available.

I would divide your problem into detection and communication. For detection, I would use a photonic detector (as suggested earlier). Then you need to communicate that to your base, and I have very little to offer in that respect.

Whatever way you go, meeting your 20 uA criterion for detection will probably be difficult.

 

hi Intruder,
Is it the same project as your other Thread.?
https://forum.allaboutcircuits.com/...agnetic-sensors-and-wireless-protocol.149723/

E
MOD:

FXOS8700CQ is much nettbe than all these and consume very less current...
But the production has been stopped by the nxp