# Wireless Module with over 1.5Km range?

I'm working with Micro Controller Mega-32 (SMD). I'm looking for a Wireless module to transfer and receive the data that I created with the micro.

Could you please guide me ?

• Just as a heads up, make sure you follow all legal regulations. Now that I have gotten that out of the way, people shouldn't need to include it in their answers. – Kellenjb Jan 31 '11 at 19:22
• On the legal front using a module can actually mitigate some issues. Under FCC at least there is a separate certification process that can grant a "Module Certification". Meaning that your final device wouldn't need to be certified as a transmitter if the module has been tested as such. That wouldn't get you out of the requirement to be certified as an incidental radiator if the rest of the device requires it but that usually isn't an issue unless selling the final product. Building a transmitter that breaks the rules can get you in trouble even if not selling it. – Mark Jan 31 '11 at 21:26

You could get to that range in the 900Mhz band with reasonable power.

LS Research makes a couple 900Mhz modules that could do it with the right antenna (directional and high gain).

Just note that usable range can vary a lot based on environment (through a city? through woods? etc).

A Candian Company called Microhard systems makes the ISM 900Mhz band radio you need.

Bit rates go from hundreds of baud to over 1.5 megabaud. Interface to your micro can be serial, USB or ethernet.

we use them on our Robots and they a have a 90-100km range. In a built up area that drops to only 30-40Km or so. If you need to you can run a radio realy an get 2-300 km range.

(Very handy for us as our biggest robot has a 300km range.)

All quite legal in any country, just say where you are and they'll send you the right radios.

• Are you sure that 1W power is legal? – Kozuch Apr 12 '16 at 0:42
• In Australia 1W in the ISM band is legal as a short range spread spectrum device in the 915-928Mhz ISM band . – Tim Williscroft Apr 13 '16 at 3:06

I've heard good things about the DNT900 from RFM. The guys over at DIY Drones say they can get it up to 40 miles at only \$69US.

we have had lots of success with the this. http://www.digi.com/products/wireless-wired-embedded-solutions/zigbee-rf-modules/point-multipoint-rfmodules/xtend-module.jsp#overview

we use it in our UAVs as a the telemetry modem. It is logic level UART and very easy to interface. We have seen performance with low gain antennas at up to 5 miles. Tested buadrate 9600.

• As it's not fair to ask irrelevant questions here, Will you please refer this thread of mine and give some suggestion.. – Anubis Aug 17 '12 at 6:32

An XBee pro (if they're still making them) might be able to achieve 1.5km with line-of-sight on the highest power rating. I think I saw them rated for 1km, so 1.5km might be a stretch, but it could be worth testing depending on how often you need to transmit.

• Could you post a reference about the XBee Pro? – Mohammad Dayyan Jan 31 '11 at 19:57
• digi.com/products/wireless/point-multipoint/… According to that, up to 1 mile range. – pfyon Jan 31 '11 at 20:12
• You probably want to look at the 900mhz line for that range: digi.com/products/wireless-wired-embedded-solutions/… – Mark Jan 31 '11 at 20:13
• @Mark, nice, I had not seen the range at that frequency. – pfyon Jan 31 '11 at 20:30
• don't get too excited by Digi's quoted range, they are...optimistic...at best. The module I linked is only a 100mW transmitter. It may get to 15 miles, in a vacuum and thats at 9.6kbps. Something like the LSR module i mentioned below can run zigbee stacks but is a 250mW transmitter and operates at up to 1Mbps. – Mark Jan 31 '11 at 20:46

I think you are out of the range of a "wireless module". I think you are getting into the realm of Long Distance WiFi.

The problem is that you need to go 1.5km. The solution would be good antennas on either end to transmit and receive the signals and a wireless radio to encode/decode the signals to bit/bytes. The actual micro you use should not matter.

• So, can I use it with my micro, Mega32 , or I have to use Computer system like a laptop? – Mohammad Dayyan Jan 31 '11 at 19:37

There are several Chinese vendors that take ISM-band chips and add a power amplifier (and sometimes LNA) to boost the range.

http://www.satistronics.com/nrf24l01-with-pa-and-lna-1000m-long-distance-24g-wireless-module-with-antenna_p2862.html

This is all of dubious legality in the US, of course. I haven't ordered any of these modules to see if they get seized by customs.

An advantage to this approach is that you can prototype with the low power device, and "upgrade" as needed.