Cheap one way RF solution

Hi all,

I am looking for a CHEAP design for RF communication.
1. The link has to be unidirectional from one microcontroller to
another.
2. The data rate requirement is not a consideration as it is very low.
3. The communication range is between 20-30 meters with obstacles like
walls in between.

I am new to RF so don't know which frequency has what advantages and
which is cheaper and legal. I am in India.
I believe I have 2 good options to work with.
1. 433Mhz
2. 2.4Ghz

Kindly suggest which would be cheaper and better suited to my needs.

Thanks,
Rohan

On 4 Mar, 08:03, "Rohan" <rohans...@gmail.com> wrote:
> Hi all,
>
> I am looking for a CHEAP design for RF communication.
> 1. The link has to be unidirectional from one microcontroller to
> another.
> 2. The data rate requirement is not a consideration as it is very low.
> 3. The communication range is between 20-30 meters with obstacles like
> walls in between.
>
> I am new to RF so don't know which frequency has what advantages and
> which is cheaper and legal. I am in India.
> I believe I have 2 good options to work with.
> 1. 433Mhz
> 2. 2.4Ghz
>
> Kindly suggest which would be cheaper and better suited to my needs.
>
> Thanks,
> Rohan

The Nordic nRF24L01 will do what you want (and a lot more besides) and
is cheap.

Leon

On Mar 4, 4:37 pm, "Leon" <leon...@btinternet.com> wrote:
> On 4 Mar, 08:03, "Rohan" <rohans...@gmail.com> wrote:
>
>
>
> > Hi all,
>
> > I am looking for a CHEAP design for RF communication.
> > 1. The link has to be unidirectional from one microcontroller to
> > another.
> > 2. The data rate requirement is not a consideration as it is very low.
> > 3. The communication range is between 20-30 meters with obstacles like
> > walls in between.
>
> > I am new to RF so don't know which frequency has what advantages and
> > which is cheaper and legal. I am in India.
> > I believe I have 2 good options to work with.
> > 1. 433Mhz
> > 2. 2.4Ghz
>
> > Kindly suggest which would be cheaper and better suited to my needs.
>
> > Thanks,
> > Rohan
>
> The Nordic nRF24L01 will do what you want (and a lot more besides) and
> is cheap.
>
> Leon

Thanks..
nRF24L01 is a Tranceiver. I believe they are more expensive than a
reciever/transmitter pair? I am not sure. Just asking you guys. Since
i want a Half Duplex path putting two tranceiver at both ends could be
more expensive.

I infer that 2.4Ghz being the most common would be really cheap.

The data rate on this chip is for VOIP level and my requirement is a
mere fraction of that. So again this chip seems a little high end for
my needs.

Any ATMEL users around?

On Mar 4, 4:37 pm, "Leon" <leon...@btinternet.com> wrote:
> On 4 Mar, 08:03, "Rohan" <rohans...@gmail.com> wrote:
>
>
>
> > Hi all,
>
> > I am looking for a CHEAP design for RF communication.
> > 1. The link has to be unidirectional from one microcontroller to
> > another.
> > 2. The data rate requirement is not a consideration as it is very low.
> > 3. The communication range is between 20-30 meters with obstacles like
> > walls in between.
>
> > I am new to RF so don't know which frequency has what advantages and
> > which is cheaper and legal. I am in India.
> > I believe I have 2 good options to work with.
> > 1. 433Mhz
> > 2. 2.4Ghz
>
> > Kindly suggest which would be cheaper and better suited to my needs.
>
> > Thanks,
> > Rohan
>
> The Nordic nRF24L01 will do what you want (and a lot more besides) and
> is cheap.
>
> Leon

Thanks..
nRF24L01 is a Tranceiver. I believe they are more expensive than a
reciever/transmitter pair? I am not sure. Just asking you guys. Since
i want a Half Duplex path putting two tranceiver at both ends could be
more expensive.

I infer that 2.4Ghz being the most common would be really cheap.

The data rate on this chip is for VOIP level and my requirement is a
mere fraction of that. So again this chip seems a little high end for
my needs.

Any ATMEL users around?

>
> I am looking for a CHEAP design for RF communication.
> 1. The link has to be unidirectional from one microcontroller to
> another.
> 2. The data rate requirement is not a consideration as it is very low.
> 3. The communication range is between 20-30 meters with obstacles like
> walls in between.
>
> I am new to RF so don't know which frequency has what advantages and
> which is cheaper and legal. I am in India.
> I believe I have 2 good options to work with.
> 1. 433Mhz
> 2. 2.4Ghz
>
I suggest 433 MHz, as 2.4 GHz does not travel well trough stone walls in my
experience. I guess some of the more optimistic numbers for 2.4 GHz come
from the US,where wall are often made of thin plasterboard.

Wim

Rohan wrote:


> I am new to RF so don't know which frequency has what advantages and
> which is cheaper and legal. I am in India.
> I believe I have 2 good options to work with.
> 1. 433Mhz
> 2. 2.4Ghz
>
> Kindly suggest which would be cheaper and better suited to my needs.

Hi, I don't know about allocations in India, but in the U.S.
there is a portion of the 27MHz 'citizen's band' that is used for
remote control and packet data. A wireless messaging device
with lots of 'aftermarket' uses by hams and others is the
Cybiko; it works on 27MHz for distances of up to 1/4 mile, has
open source software (and closed source development kit),
schematics, etc. You might also consider 49MHz (also a remote
control allocation) if permitted in India.

Regards,

Michael

Hello Rohan,

What kind of controller are you using? I have some simplex/duplex code for a
PCA equipped Atmel 8052 that works just as well in a simplex configuration.
I used super cheap TWS-434A transmitter and RWS-434 receiver modules that
operate in 1200 bps CW mode. Not too sure about the range, but you should
get 20m with a brick wall in the way okay. Check my homepage listed below if
you think that might help.

--
32°02'14.23"S 115°53'21.30"E
http://www.review-a-gadget.com/
http://members.iinet.net.au/~vanluynm/

"Rohan" <> wrote in message
news: oups.com...
> Hi all,
>
> I am looking for a CHEAP design for RF communication.
> 1. The link has to be unidirectional from one microcontroller to
> another.
> 2. The data rate requirement is not a consideration as it is very low.
> 3. The communication range is between 20-30 meters with obstacles like
> walls in between.
>
> I am new to RF so don't know which frequency has what advantages and
> which is cheaper and legal. I am in India.
> I believe I have 2 good options to work with.
> 1. 433Mhz
> 2. 2.4Ghz
>
> Kindly suggest which would be cheaper and better suited to my needs.
>
> Thanks,
> Rohan
>

On Mar 4, 1:03 pm, "Rohan" <> wrote:
> Hi all,
>
> I am looking for a CHEAP design for RF communication.
> 1. The link has to be unidirectional from one microcontroller to
> another.
> 2. The data rate requirement is not a consideration as it is very low.
> 3. The communication range is between 20-30 meters with obstacles like
> walls in between.
>
> I am new to RF so don't know which frequency has what advantages and
> which is cheaper and legal. I am in India.
> I believe I have 2 good options to work with.
> 1. 433Mhz
> 2. 2.4Ghz
>
> Kindly suggest which would be cheaper and better suited to my needs.
>
> Thanks,
> Rohan

Hi Rohan,

Atmel has series of Transmitters / Receivers for Automotive control
i.e. Tire Pressure Monitoring System look at the following link

http://www.atmel.com/dyn/products/de...?family_id=606

Rohan wrote:
> On Mar 4, 4:37 pm, "Leon" <leon...@btinternet.com> wrote:
>> On 4 Mar, 08:03, "Rohan" <rohans...@gmail.com> wrote:
>>
>>
>>
>>> Hi all,
>>> I am looking for a CHEAP design for RF communication.
>>> 1. The link has to be unidirectional from one microcontroller to
>>> another.
>>> 2. The data rate requirement is not a consideration as it is very low.
>>> 3. The communication range is between 20-30 meters with obstacles like
>>> walls in between.
>>> I am new to RF so don't know which frequency has what advantages and
>>> which is cheaper and legal. I am in India.
>>> I believe I have 2 good options to work with.
>>> 1. 433Mhz
>>> 2. 2.4Ghz
>>> Kindly suggest which would be cheaper and better suited to my needs.
>>> Thanks,
>>> Rohan
>> The Nordic nRF24L01 will do what you want (and a lot more besides) and
>> is cheap.
>>
>> Leon
>
> Thanks..
> nRF24L01 is a Tranceiver. I believe they are more expensive than a
> reciever/transmitter pair? I am not sure. Just asking you guys. Since
> i want a Half Duplex path putting two tranceiver at both ends could be
> more expensive.
>

You don't get receiver-only devices. There are transmitter-only, and
transceiver types. Transmitter-only are now less common - they are not
much cheaper than transceivers, and it's often nice to have a little
feedback (blinking LED, for example).

> I infer that 2.4Ghz being the most common would be really cheap.
>
> The data rate on this chip is for VOIP level and my requirement is a
> mere fraction of that. So again this chip seems a little high end for
> my needs.
>
> Any ATMEL users around?
>

On Mar 8, 7:27 am, David Brown

> You don't get receiver-only devices. There are transmitter-only, and

That isn't even vaguely true. RFMD, Philips, Melexis, Atmel,
Microchip, ... all make receive-only devices. Not only are they
cheaper, they're also cheaper to integrate due to fewer and simpler
external components.

RKE applications, for instance, have absolutely no use for a
transceiver.