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UMTS-GSM Guardband

Viewing 8 posts - 1 through 8 (of 8 total)
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  • #69123
    Jason
    Guest

    Hello;
    I was under the impression that there needs to be a guard band between UMTS and GSM. Is this true or false?
    Thanks in advance
    Jason

    #69124
    pix
    Guest

    Hi,

    UMTS 900 is located on the same band as GSM 900.

    You have to dissociate the technology (UMTS) from the band being used (2100, 800, 900, …)

    Regards
    pix

    #69125
    Jason
    Guest

    Thanks Pix,
    I dont really understand what your saying exacly. We currently would like GSM and UMTS on consecutive blocks of frequency with out any guard band between for example perhaps a 200 kHz guard band. I am not sure this would work. have you done this?

    #69126
    Jason
    Guest

    I have just heard from a friend that we should have 1Mhz between our GSM and UMTS frequencys.

    #69127
    pix
    Guest

    hi jason,

    My initial post was actually asking in which frequency band you werre working. I assume you’re talking about GSM900 and UMTS900 co-existance ?

    In this case, 3GPP said that a guard band of 300 kHz is enough. One GSM chanel = 200kHz, so you’re fine if you keep 2 arfcn (400kHz) separation between the start/end of UMTS 5MHz bw and the first used GSM channel.

    If you want to read : 3GPP TR 25.816

    Maybe I’m wrong, but I think the operator for which I’m working for at the moment is only using 200kHz guard band. This has to be confirmed.

    Cheers,
    Pix

    #69128
    Jason
    Guest

    Thanks Pix,
    We are running both of these on 850.

    I appriciate the help.
    Jason

    #69129
    pix
    Guest

    ok, 850 *should* be the same. I’m quite sure the 3GPP did the same kind of study for 850 too, but it’s for you to find it 🙂

    Regards
    pix

    #69130
    Mazahir
    Guest

    Hello,

    Actually it depends on vendor and HW specification as well.

    Because according to Nokia recommendation , there is Sandwich-type frequency allocation which allows even to use last 200 KHZ frequencies from each end as GSM TCH frequency (in 4.4 MHZ).

    Thanks,

    Mazahir

Viewing 8 posts - 1 through 8 (of 8 total)
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