Wireless question - Vince
Archiver
Posts: 46,084
Vince,
Your question is essentially a telecoms question and remote
monitoring/control.
Distances of 1/2 mile are typically covered by leased line from the
PTT if the land in-between is private/public property.
If the distance is all on land under your own control, a landline
(ie, buried cable) is the most common form of communication. Suitable
underground armoured cables are available commercially, as are
armoured fibre optic lines.
If your data is very short bursts and very intermittant in nature
(your original post suggests it may be) and the terrain is line-of-
sight, then you may perhaps consider a low power radio/microwave link.
Such equipment can be expensive, but at say, 2.4GHz (=2400 MHz) and a
decent yagi antenna you should cover the distance with only a few
watts of power.
Licencing and regulatory aspects will determine the frequency and
power you are allowed to use.
Firstly, I would suggest you look at the data rate you require to
achieve your control goal (include the read-back and error correction
also!).
I would perhaps firstly consider landline and armored cable, backed
up with a simple low datarate RF link. Such links are commercially
available, and are in use by most of the utilities companies(gas,
water, elec, etc) as well as the telco's for rural connection of
phone lines. Equipment may be advertised as "WLL" (for wireless local
loop) on occasion. This effectively offers (multiple)
56kbps "analogue" telephone lines over an area (typically 2km) and is
commonly in use in many low population-density areas of the US and
Africa for telecoms. The term "local loop" or "last mile" refers to
the connection from the telephone exchange to the customer. It refers
to the last part of a telephone connection (or IP, data etc) from the
telco's premises to the end customer.
Best wishes,
Dare
--- In basicstamps@y..., "Fell, Vince" <vince.fell@t...> wrote:
> Sid,
> Thanks for the reply.
> You are correct in that the communications part of the equation may
be the
> toughest to whip.
> The area between the station/substations are relatively flat and
level. With
> few to no obstructions. Power is available at all stations. Relay
stations
> would not be feasable for a number of reasons.
> Thanks again.
> VF
>
>
Original Message
> From: Newzed@a... [noparse][[/noparse]mailto:Newzed@a...]
> Sent: Thursday, July 18, 2002 2:13 PM
> To: basicstamps@y...
> Subject: Re: [noparse][[/noparse]basicstamps] Wireless question
>
>
> For Vince
>
> I can write a program that will accomplish what you want, but as
you point
> out, interstation communication is the problem. What is the
topography
> between the main and sub-stations ? Where do A and B get their
power from ?
> Are "relay" stations feasible ?
>
> RF equipment to cover that distance is available but quite
expensive.
>
> I have written several programs using RF and IR for remote control
of relays
>
> but all for shorter disances.
>
> Sid
>
>
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@y...
> from the same email address that you subscribed. Text in the
Subject and
> Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
Your question is essentially a telecoms question and remote
monitoring/control.
Distances of 1/2 mile are typically covered by leased line from the
PTT if the land in-between is private/public property.
If the distance is all on land under your own control, a landline
(ie, buried cable) is the most common form of communication. Suitable
underground armoured cables are available commercially, as are
armoured fibre optic lines.
If your data is very short bursts and very intermittant in nature
(your original post suggests it may be) and the terrain is line-of-
sight, then you may perhaps consider a low power radio/microwave link.
Such equipment can be expensive, but at say, 2.4GHz (=2400 MHz) and a
decent yagi antenna you should cover the distance with only a few
watts of power.
Licencing and regulatory aspects will determine the frequency and
power you are allowed to use.
Firstly, I would suggest you look at the data rate you require to
achieve your control goal (include the read-back and error correction
also!).
I would perhaps firstly consider landline and armored cable, backed
up with a simple low datarate RF link. Such links are commercially
available, and are in use by most of the utilities companies(gas,
water, elec, etc) as well as the telco's for rural connection of
phone lines. Equipment may be advertised as "WLL" (for wireless local
loop) on occasion. This effectively offers (multiple)
56kbps "analogue" telephone lines over an area (typically 2km) and is
commonly in use in many low population-density areas of the US and
Africa for telecoms. The term "local loop" or "last mile" refers to
the connection from the telephone exchange to the customer. It refers
to the last part of a telephone connection (or IP, data etc) from the
telco's premises to the end customer.
Best wishes,
Dare
--- In basicstamps@y..., "Fell, Vince" <vince.fell@t...> wrote:
> Sid,
> Thanks for the reply.
> You are correct in that the communications part of the equation may
be the
> toughest to whip.
> The area between the station/substations are relatively flat and
level. With
> few to no obstructions. Power is available at all stations. Relay
stations
> would not be feasable for a number of reasons.
> Thanks again.
> VF
>
>
Original Message
> From: Newzed@a... [noparse][[/noparse]mailto:Newzed@a...]
> Sent: Thursday, July 18, 2002 2:13 PM
> To: basicstamps@y...
> Subject: Re: [noparse][[/noparse]basicstamps] Wireless question
>
>
> For Vince
>
> I can write a program that will accomplish what you want, but as
you point
> out, interstation communication is the problem. What is the
topography
> between the main and sub-stations ? Where do A and B get their
power from ?
> Are "relay" stations feasible ?
>
> RF equipment to cover that distance is available but quite
expensive.
>
> I have written several programs using RF and IR for remote control
of relays
>
> but all for shorter disances.
>
> Sid
>
>
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@y...
> from the same email address that you subscribed. Text in the
Subject and
> Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
Comments
wireless cards ($30) and some homebrew cantennas ($20 or so)? You'll get the
range easily and it will be reliable and, with a little bit of work, secure.
You'll need to do a little bit of software work to get the Stamps working
across the link but it shouldn't be too bad.
Check http://www.turnpoint.net/wireless/cantennahowto.html
Best,
Sanjay
1.415.577.8099 (cell)
Original Message
From: "dare2care4today" <dare@s...>
To: <basicstamps@yahoogroups.com>
Sent: Friday, July 19, 2002 4:51 AM
Subject: [noparse][[/noparse]basicstamps] Re: Wireless question - Vince
>
> Vince,
>
> Your question is essentially a telecoms question and remote
> monitoring/control.
>
> Distances of 1/2 mile are typically covered by leased line from the
> PTT if the land in-between is private/public property.
>
> If the distance is all on land under your own control, a landline
> (ie, buried cable) is the most common form of communication. Suitable
> underground armoured cables are available commercially, as are
> armoured fibre optic lines.
>
> If your data is very short bursts and very intermittant in nature
> (your original post suggests it may be) and the terrain is line-of-
> sight, then you may perhaps consider a low power radio/microwave link.
>
> Such equipment can be expensive, but at say, 2.4GHz (=2400 MHz) and a
> decent yagi antenna you should cover the distance with only a few
> watts of power.
>
> Licencing and regulatory aspects will determine the frequency and
> power you are allowed to use.
>
> Firstly, I would suggest you look at the data rate you require to
> achieve your control goal (include the read-back and error correction
> also!).
>
> I would perhaps firstly consider landline and armored cable, backed
> up with a simple low datarate RF link. Such links are commercially
> available, and are in use by most of the utilities companies(gas,
> water, elec, etc) as well as the telco's for rural connection of
> phone lines. Equipment may be advertised as "WLL" (for wireless local
> loop) on occasion. This effectively offers (multiple)
> 56kbps "analogue" telephone lines over an area (typically 2km) and is
> commonly in use in many low population-density areas of the US and
> Africa for telecoms. The term "local loop" or "last mile" refers to
> the connection from the telephone exchange to the customer. It refers
> to the last part of a telephone connection (or IP, data etc) from the
> telco's premises to the end customer.
>
> Best wishes,
>
> Dare
>
> --- In basicstamps@y..., "Fell, Vince" <vince.fell@t...> wrote:
> > Sid,
> > Thanks for the reply.
> > You are correct in that the communications part of the equation may
> be the
> > toughest to whip.
> > The area between the station/substations are relatively flat and
> level. With
> > few to no obstructions. Power is available at all stations. Relay
> stations
> > would not be feasable for a number of reasons.
> > Thanks again.
> > VF
> >
> >
Original Message
> > From: Newzed@a... [noparse][[/noparse]mailto:Newzed@a...]
> > Sent: Thursday, July 18, 2002 2:13 PM
> > To: basicstamps@y...
> > Subject: Re: [noparse][[/noparse]basicstamps] Wireless question
> >
> >
> > For Vince
> >
> > I can write a program that will accomplish what you want, but as
> you point
> > out, interstation communication is the problem. What is the
> topography
> > between the main and sub-stations ? Where do A and B get their
> power from ?
> > Are "relay" stations feasible ?
> >
> > RF equipment to cover that distance is available but quite
> expensive.
> >
> > I have written several programs using RF and IR for remote control
> of relays
> >
> > but all for shorter disances.
> >
> > Sid
> >
> >
> >
> >
> > [noparse][[/noparse]Non-text portions of this message have been removed]
> >
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@y...
> > from the same email address that you subscribed. Text in the
> Subject and
> > Body of the message will be ignored.
> >
> >
> > Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
>