Hi

I am working on point to point communication system over dedicated coaxial cable.

Required Data rate = 100kbps
cable length = 5km

I am looking for suggestion/design ideas

In one of my previous projects I used wire line modem (CMX866) successfully over similar distance but baud rate was 2400.

Can I use two DSL modem ICs for such communication? are DSL chipset ICs available for Digikey/Farnell? i couldn't find any from product profile of TI, Analog or ST etc.
I know Broadcomm is a key player in this market but they don't have good reputation for supporting small volume/ niche market customers.


Any other ideas?


Thanks

mmuj

 

Three miles of cable? Really?

 

Can you specify the coaxial cable and the carrier frequency?
If so I would suggest 75 Ohm CATV coax and 300-800 MHz.
You might need to use either repeaters or substantial power levels.
Industrial grade RF modems should work for you.

 

Required distance is over 3 miles on an existing coaxial like cable, and to though spanner in the work, with the temperature range of at
least 150C.

Thnks Papabravo, can you suggest any suitable chip for FR modem type communication?

I also thought about using Power line solution from TI using AFE031.

 

I wasn't thinking of chips, but rather complete modules. Doing an RF modem is not a single chip affair, there is more to it, not to mention the cost of the test equipment you'll need.

 

The 150 Degrees C. spec is a bitch.

How about sending the signal as base-band serial data?
Attenuation in coax is proportional to frequency, direct signaling minimizes the loss.

 

The 150 Degrees C. spec is a bitch.

Not if you build the entire system out of high power MOSFETS and dual Shottkey rectifiers. But other than that, I gotta ask - what task is 3 miles long and 300 F? Distributed sensors around the rim of an active volcano? Inquiring minds...

ak

 

Hi

I am working on point to point communication system over dedicated coaxial cable.

Required Data rate = 100kbps
cable length = 5km

I am looking for suggestion/design ideas

In one of my previous projects I used wire line modem (CMX866) successfully over similar distance but baud rate was 2400.

Can I use two DSL modem ICs for such communication? are DSL chipset ICs available for Digikey/Farnell? i couldn't find any from product profile of TI, Analog or ST etc.
I know Broadcomm is a key player in this market but they don't have good reputation for supporting small volume/ niche market customers.


Any other ideas?


Thanks

mmuj

it's commercial available look at https://www.scribd.com/doc/114590501/DSL-leased-line-modem-Realgain-4

 

Is Fiber Optics an option?

 

Not if you build the entire system out of high power MOSFETS and dual Shottkey rectifiers. But other than that, I gotta ask - what task is 3 miles long and 300 F? Distributed sensors around the rim of an active volcano? Inquiring minds...

ak

You are not that far off

Is Fiber Optics an option?

it is a last option

 

You are not that far off
it is a last option

Is this for some down-hole logging tool?