433MHz remotes with >500ft range

[Joerg]

Hi guys,

Somehow most companies offer all sorts of modules but no "ready-to-sell"
remotes that are a tad above the performance of keyfobs. What I am
looking for:

3 buttons, custom overlay.
International approvals (meaning 433MHz or 2.45GHz).
<$20/1k, yearly volume several k.
Outdoor range a reliable 500ft, ideally more.
Customizeable codes.
Works together with a low cost chipset, for example from TI.
Size max 1.5" by 2", 1/2" high, plus belt clip.
Integrated stub antenna can be another inch or so.
Very sturdy, for example ABS.

I am aware of the Linx brand. Any others? Ideally we'd want to make sure
two brands work so we have a 2nd source situation.

Copied c.a.embedded because there may be folks who deal with radio
controlled embedded systems.

 

[TTman]

Hi guys,

Somehow most companies offer all sorts of modules but no "ready-to-sell"
remotes that are a tad above the performance of keyfobs. What I am
looking for:

3 buttons, custom overlay.
International approvals (meaning 433MHz or 2.45GHz).
<$20/1k, yearly volume several k.
Outdoor range a reliable 500ft, ideally more.
Customizeable codes.
Works together with a low cost chipset, for example from TI.
Size max 1.5" by 2", 1/2" high, plus belt clip.
Integrated stub antenna can be another inch or so.
Very sturdy, for example ABS.

I am aware of the Linx brand. Any others? Ideally we'd want to make sure
two brands work so we have a 2nd source situation.

Copied c.a.embedded because there may be folks who deal with radio
controlled embedded systems.

Has to be 433 for 500ft I would have thought......I use Nordic nrf905....

 

[Paul Keinanen]

Hi guys,

Somehow most companies offer all sorts of modules but no "ready-to-sell"
remotes that are a tad above the performance of keyfobs. What I am
looking for:

3 buttons, custom overlay.
International approvals (meaning 433MHz or 2.45GHz).
<$20/1k, yearly volume several k.
Outdoor range a reliable 500ft, ideally more.
Customizeable codes.

You should also check how the link performs with nearby 5-50 W
transmitters on the same or nearby (hundreds of kHz) frequency as your
433 MHz link.

In Europe, the 433 ISM band is in the actively used part of the 70 cm
amateur radio band, so quite strong signals may also be present at
that band.

At least the old keyfob system receivers had very bad selectivity,
getting blocked by transmitters hundreds of kHz away. A person is
approaching his/her car, a nearby handheld amateur radio transceiver
is activated and the operator describes what the car owner is doing,
when the doors do not open, people seem to do all kind of funny thing,
when trying to get the car open with the remote control .

 

[JB]

Hi guys,

Somehow most companies offer all sorts of modules but no "ready-to-sell"
remotes that are a tad above the performance of keyfobs. What I am
looking for:

<snip>

Speak to John Fairall at RF Solutions here in the UK. They have such a
product range.
http://www.rfsolutions.co.uk/

JB

 

[I AM THAT I AM]

Hi guys,

Somehow most companies offer all sorts of modules but no "ready-to-sell"
remotes that are a tad above the performance of keyfobs. What I am
looking for:

3 buttons, custom overlay.
International approvals (meaning 433MHz or 2.45GHz).
<$20/1k, yearly volume several k.
Outdoor range a reliable 500ft, ideally more.
Customizeable codes.
Works together with a low cost chipset, for example from TI.
Size max 1.5" by 2", 1/2" high, plus belt clip.
Integrated stub antenna can be another inch or so.
Very sturdy, for example ABS.

I am aware of the Linx brand. Any others? Ideally we'd want to make sure
two brands work so we have a 2nd source situation.

Copied c.a.embedded because there may be folks who deal with radio
controlled embedded systems.

$20 each for a custom controller? Ha!

More like $200 to $400 depending on options.


http://www.avalonrf.com/products/digital-data-links/250mw-wireless-digital-link

 

[I AM THAT I AM]

$20 each for a custom controller? Ha!

More like $200 to $400 depending on options.


http://www.avalonrf.com/products/digital-data-links/250mw-wireless-digital-link

Also, very rarely do any two brands work together in this business. So
they will not be providing IP for 'second sources' to profit from.

There are no standards and no consortiums for any that I know of.

 

[Joerg]

Has to be 433 for 500ft I would have thought......I use Nordic nrf905....

Thanks, but that's a module and we are looking for a complete packaged
product, with the required papers from agency approval labs.

 

[Joerg]

You should also check how the link performs with nearby 5-50 W
transmitters on the same or nearby (hundreds of kHz) frequency as your
433 MHz link.

In Europe, the 433 ISM band is in the actively used part of the 70 cm
amateur radio band, so quite strong signals may also be present at
that band.

At least the old keyfob system receivers had very bad selectivity,
getting blocked by transmitters hundreds of kHz away. A person is
approaching his/her car, a nearby handheld amateur radio transceiver
is activated and the operator describes what the car owner is doing,
when the doors do not open, people seem to do all kind of funny thing,
when trying to get the car open with the remote control .

Yes, Paul, I know. But what can one do? Europe doesn't allow the VHF
bands we have here and the only common denominators worldwide are 433MHz
and 2.45GHz. 2.45GHz often has range problems.

 

[Joerg]

<snip>

Speak to John Fairall at RF Solutions here in the UK. They have such a
product range.
http://www.rfsolutions.co.uk/

Thanks, I will. They have a US distributor and their products look a bit
more bulky but I'll ask if they can supply one that sort of matches:

http://www.okwelectronics.com/products/rfsolutions/remote_controls/fm_remote_controls-menu.htm

 

[dalai lamah]

Un bel giorno Joerg digitò:

International approvals (meaning 433MHz or 2.45GHz). [...]
Outdoor range a reliable 500ft, ideally more.

EU regulations mandate a maximum transmit power of 10 mW eirp at 433 MHz
for SRDs (short range devices). It is almost impossible to reach 150 m with
this power in a reliable way, unless you have a directional antenna and a
perfect line of sight (two things you can't rely on with a typical key fob
application). With these regulations and a good antenna you can get a
"real-life" reliable range of 50-70 m.

At 2450 MHz you can qualify your device as a "radio frequency
identification device" rather than a generic short range device. This
allows you to use powers up to 500 mW. To get 150 meters in a reliable way
at 2450 MHz you will need a lot of power though, and this isn't good for a
battery powered key fob.

 

[tm]

Un bel giorno Joerg digitò:

International approvals (meaning 433MHz or 2.45GHz). [...]
Outdoor range a reliable 500ft, ideally more.

EU regulations mandate a maximum transmit power of 10 mW eirp at 433 MHz
for SRDs (short range devices). It is almost impossible to reach 150 m
with
this power in a reliable way, unless you have a directional antenna and a
perfect line of sight (two things you can't rely on with a typical key fob
application). With these regulations and a good antenna you can get a
"real-life" reliable range of 50-70 m.

Even with a "good antenna" you are still fixed to +10 dBm EIRP. Maybe with
the
receiver having the good antenna, you can get better range but then it will
make
the receiver directional. About the only way around this is to use a slow
data rate
and very narrow bandwidth such as to lower the noise floor and improve the
system gain.

tm

 

[Joerg]

Un bel giorno Joerg digitò:

International approvals (meaning 433MHz or 2.45GHz). [...]
Outdoor range a reliable 500ft, ideally more.

EU regulations mandate a maximum transmit power of 10 mW eirp at 433 MHz
for SRDs (short range devices). It is almost impossible to reach 150 m with
this power in a reliable way, unless you have a directional antenna and a
perfect line of sight (two things you can't rely on with a typical key fob
application). With these regulations and a good antenna you can get a
"real-life" reliable range of 50-70 m.

Yeah, sometimes I wonder what the guys in Brussels were thinking. Or
whether they were thinking ...

EU operation on 433MHz would almost mandate AM mode and then tons of
correlation. All we need is slow push-button control so an effective
data rate of 10 bits per second or even less would be fine.

At 2450 MHz you can qualify your device as a "radio frequency
identification device" rather than a generic short range device. This
allows you to use powers up to 500 mW. To get 150 meters in a reliable way
at 2450 MHz you will need a lot of power though, and this isn't good for a
battery powered key fob.

AFAIK they even have a 4W category when not inside buildings but that
would require some massive battery. And we can't have that.

 

[Rich Grise]

Yes, Paul, I know. But what can one do? Europe doesn't allow the VHF
bands we have here and the only common denominators worldwide are 433MHz
and 2.45GHz. 2.45GHz often has range problems.

"Range" problems? Since that's close to the microwave oven freq's, there's
got to be some kind of joke in there.

(In America, a "range" is an oven with a stove on top.)

Cheers!
Rich

 

[Spehro Pefhany]

"Range" problems? Since that's close to the microwave oven freq's, there's
got to be some kind of joke in there.

(In America, a "range" is an oven with a stove on top.)

Suitable for cooking venison and antelope meat?

 

[Rich Grise]

Suitable for cooking venison and antelope meat?

And seldom is heard
A discourging word,
Because what can an antelope say? ;-)

Cheers!
Rich

 

[I AM THAT I AM]

That is true, but many employ the usual Asian chips for encoding and the
RF part itself is nothing more than a transmitter with a modulator.
That's the kind we are after because then the code is the same, as long
as both use FM or whatever modulation scheme.

The Avalon RF stuff uses a QAM256 encapsulation.

The whole idea was to alleviate the dropouts that occur with
Std FM stuff. It is like the DTV version of a stage microphone with very
little latency, yet fully digitized, packetized, and encrypted, if need
be.

We did a test where we replaced the reel-to-reel recorders on carriers
with a belt worn "DVR" and all the deck traffic spoke through those
links. All was recorded on the recorder device, and the Air Boss got
clean feeds all the time without dropouts. It was pretty cool.
Integrated it all into the colored deck vests and helmets they wear while
up on the flight decks.

 

[I AM THAT I AM]

Un bel giorno Joerg digitò:

International approvals (meaning 433MHz or 2.45GHz). [...]
Outdoor range a reliable 500ft, ideally more.

EU regulations mandate a maximum transmit power of 10 mW eirp at 433 MHz
for SRDs (short range devices). It is almost impossible to reach 150 m
with
this power in a reliable way, unless you have a directional antenna and a
perfect line of sight (two things you can't rely on with a typical key fob
application). With these regulations and a good antenna you can get a
"real-life" reliable range of 50-70 m.

Even with a "good antenna" you are still fixed to +10 dBm EIRP. Maybe with
the
receiver having the good antenna, you can get better range but then it will
make
the receiver directional. About the only way around this is to use a slow
data rate
and very narrow bandwidth such as to lower the noise floor and improve the
system gain.

tm

Or use diversity.

 

[Paul Keinanen]

Un bel giorno Joerg digitò:

International approvals (meaning 433MHz or 2.45GHz). [...]
Outdoor range a reliable 500ft, ideally more.

EU regulations mandate a maximum transmit power of 10 mW eirp at 433 MHz
for SRDs (short range devices). It is almost impossible to reach 150 m with
this power in a reliable way, unless you have a directional antenna and a
perfect line of sight (two things you can't rely on with a typical key fob
application). With these regulations and a good antenna you can get a
"real-life" reliable range of 50-70 m.

Yeah, sometimes I wonder what the guys in Brussels were thinking. Or
whether they were thinking ...

It is a question of frequency reuse and the difference in population
densities.

The radio frequency spectrum is a limited natural recourse and thus as
many communication links should be able to use the same frequency. On
HF (especially in the 10-20 MHz) range, the reuse factor can be as low
as 3 due to the ionospheric propagation (i.e. there can be only 3
independent communication links at a specific frequency globally at
similar power levels). On VHF/UHF/SHF the communication range is
mainly limited due to geometry to distances of 30-100 km, thus, the
global reuse factor is significantly larger.

By limiting the transmitter power, the reuse factor can be much
larger, i.e. more devices will fit into the same frequency range.

The free space loss is inversely proportional to the square of
distance, while in urban environment, the received power is inversely
proportional to the 4th power of distance. Thus, with transmitters and
receivers well below the roof line, the propagation distance is quite
limited and a large number of SRDs can be used on a single frequency.

In Europe, the population density is high in most of Central Europe,
while in the USA, the population densities outside New England and
some metropolitan areas is quite low. Thus, a lower frequency reuse
would make sense in most of USA (i.e. allowing higher power levels).

I do not want to defend traditional channel exclusive allocation
systems, since a frequency range is unused most of the time. It makes
much more sense to use some kind of ALE (Automatic Link Establishment)
or some frequency agile system (like CDMA) to get the message trough.

I do not know, if the row about using unused UHF TV channels in the
USA for other communication has bee solved, but this at least shows
the problems of packing as much as possible communication into a
limited frequency range.

IMO, radio communication should be used only when it is absolutely
necessary (e.g. moving platforms), but as soon as the signal is within
a fixed wire/fiber network, the signal should be transferred to the
wire, freeing up the radio frequency for other users.

 

[Paul Keinanen]

The Avalon RF stuff uses a QAM256 encapsulation.

This requires a quite high SNR.

The whole idea was to alleviate the dropouts that occur with
Std FM stuff. It is like the DTV version of a stage microphone with very
little latency, yet fully digitized, packetized, and encrypted, if need
be.

Unless you are using some kind of FHSS/DSSS system, the latency would
be quite large due to the need for using interleaving.

 

[Tim Williams]

Suitable for cooking venison and antelope meat?

No, measuring resistances... "Ohm, ohm on the range..."

Tim