Low power RF solution
Low power RF solution
(OP)
I'm fairy new to eng-tips so not sure if this is the best forum.
But can anyone recomend the best tecnology to go for a short range short burst RF data link, we were looking at an RF PIC system 433MHz but this would seem to be unsupported, A customer has suggested zigbee but we wonder if this is overkill.
Bert.
But can anyone recomend the best tecnology to go for a short range short burst RF data link, we were looking at an RF PIC system 433MHz but this would seem to be unsupported, A customer has suggested zigbee but we wonder if this is overkill.
Bert.





RE: Low power RF solution
1) What is the volume? Unless you are making more than around 10K units, it's probably best to buy someone’s pre-made module. This is because of the time to design and agency approval issues.
2) What is the range needed? Through what kind of obstacles? How big a space do you have for your antenna? These issues affect “link margin” which determine how much power you must transmit and sensitive your receiver will need to be.
3) How reliable does the link have to be? Does it matter if a few transmissions are missed? In other words, if your wireless link closes the loop in a process system, the link must be robust, reliable under all conditions, probably will require receipt acknowledgements, and contain error correction. If the data is for a less critical use, then a missed data packet will probably not be important and latency may not be an issue. This issue will also influence the best type of modulation to use and the networking
4) Does the application require battery power? Battery operated data links cannot be ON all the time. This then requires synchronizing the ends of data link and what kind of networking layer you may need to consider.
5) How much data are you communicating in each burst? A few bytes? A few Kbytes? Zigbee/802.15.4 are good for a few tens of bytes. If you are trying to do digital audio or video, then you’re looking at something more like wireless LAN or Bluetooth.
Within Engineering tips, there is also an Antenna and Propagation Engineering Forum and a Microwave and Electromagnetic Engineering Forum.
RE: Low power RF solution
berty1971; Several times I have been able to solve short range RF problems, circumventing the whole miserable bureaucracy of regulations by using IR com links. So you should consider if this would be viable too.
RE: Low power RF solution
few kbps?
ask, ook modulation up to 300 m open ground
try this:
laipac.com
abacomtech.com
just plug and play.
id like to know what are you doing to help you
best
killa
RE: Low power RF solution
collimator lenses 300m shouldn't be difficult with LED
-- i.e. without laser . I suggest a carrier of a few
tenthousand Hz-s.
With IR you need error correction/detection.
What about weather if outdoors ?
<nbucska@pc33peripherals.com> omit 33 Use subj: ENG-TIPS
Plesae read FAQ240-1032
RE: Low power RF solution
RE: Low power RF solution
do you use few leds in paralell?
what kind of driver and receiver you know?
regards
killa
RE: Low power RF solution
the wall reflection questionable...
Killa:
You can use e.g. QED234-ND IR LED from <DIGIKEY.COM>
which can take max. 200mA at 50% duty cycle
Radio Shack has a 38 kHz ir receiver, but it is too slow
for your need.
The circuit: TX: LTC6900 silicon oscillator with some
buffer and LED
RX: photo detector , narrow band AC amplifier,
amplitude detector.
<nbucska@pc33peripherals.com> omit 33 Use subj: ENG-TIPS
Plesae read FAQ240-1032
RE: Low power RF solution
RE: Low power RF solution
I assumed to be valid. Just confusion.
berty:
Could you please specify your need?
Killa:
If you are working on a similar project, why don'y you
start a new thread?
<nbucska@pc33peripherals.com> omit 33 Use subj: ENG-TIPS
Plesae read FAQ240-1032
RE: Low power RF solution
just if anyone of you know about electric or electronic low pressura gas propane valve or regulator?
regards