Differences between usrps

hi,

as some of you already know, i have a usrp1 with 2 rfx1800 burned to
rfx900, two small antenas (13db, 60 watts) and a stock clock of 64mhz
which i’m planning to change for the external clocktamer. however,
before i do that, i’d like to know which is the best option for me.

  1. as i understand, the main difference between usrp1 and usrp n210 is
    the frequency range. does this have to do with the capacity for
    concurrent calls? is this why the usrp1 can have 7 concurrent calls
    while the usrp n210 can have up to 12 concurrent calls (without further
    modification)?

  2. also, i’d like to know what would be the reach of my system in open
    field. i guess, as i now have it, would be around 200 meters, so if i
    would like to improve that i would need either a filter (for transmit
    and receive?) or a duplexer and a higher power antena?

  3. what is the ethernet connection in the usrp n210 for?

  4. if i would like to increase the number of concurrent calls, i guess i
    would need to buy more usrps, which ones would be better to achieve a
    higher number of concurrent calls? ie, which is designed to be able to
    connect to other usrps and increase the number of concurrent calls?

thanks in advance,

On 09/06/2011 08:27 AM, Walter B. wrote:

while the usrp n210 can have up to 12 concurrent calls (without further
modification)?
Not frequency range. The USRP1 and USRP2/N210 family will operate over
identical frequency
ranges for the same daughtercards. But the instantaneous bandwidth
towards the host is
higher with the N210 (25Msps vs 8Msps), so depending on the channel
allocation scheme of
whatever your application is, this can allow more channels.

  1. also, i’d like to know what would be the reach of my system in open
    field. i guess, as i now have it, would be around 200 meters, so if i
    would like to improve that i would need either a filter (for transmit
    and receive?) or a duplexer and a higher power antena?
    You’d need a power amplifier and duplexor arrangement, likely. But that
    would take
    an operation that is already on the edge of legality, and make it
    utterly illegal in
    most places, since you’d be interfering with licensed services (the
    GSM operators).
  1. what is the ethernet connection in the usrp n210 for?
    The ethernet connection is how samples go into/out-of the N210. On the
    USRP1, those samples
    are carried over USB.
  1. if i would like to increase the number of concurrent calls, i guess i
    would need to buy more usrps, which ones would be better to achieve a
    higher number of concurrent calls? ie, which is designed to be able to
    connect to other usrps and increase the number of concurrent calls?

thanks in advance,

That’s a question for the OpenBTS list. OpenBTS is one of hundreds of
different applications extant for
Gnu Radio and the USRP family of digital transceivers. Direct
OpenBTS questions to the appropriate list.


Marcus L.
Principal Investigator
Shirleys Bay Radio Astronomy Consortium