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  1. #1
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    doubt on RF repeater IC's

    i have taken over a project on RF repeater for mobile communication, which shall be useful in ares with less network coverage. the chain is
    RF signal -> Duplexer -> SAW filter -> LNA -> PA
    I need RF IC's for all the above. Can any one suggest which IC's shall suit the above approach?

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    Re: doubt on RF repeater IC's

    You have to be far more specific:

    what frequency?
    what input signal strength?
    what output power?
    what bandwidth/type of modulation?
    Is the frequency shifted?

    Brian.
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    It's better to share your questions and answers on Edaboard so we can all benefit from each others experiences.



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    Re: doubt on RF repeater IC's

    Quote Originally Posted by betwixt View Post
    You have to be far more specific:

    what frequency?
    what input signal strength?
    what output power?
    what bandwidth/type of modulation?
    Is the frequency shifted?

    Brian.
    Actually i am designing initially a monopole to receive signals from the roof then there has to be an amplifier and band pass filter attached with it, the amplified signal will be given to another monopole antenna that will re-radiate the signal in that small area having less signal. This setup was for receiving the signals, a similar arrangement is to be done for transmitting those signals. So i need to design two pairs of amplifier and band pass filter of GSM band i.e. the uplink frequency range is 933-960 MHz and downlink is 890-915 MHz. For these frequencies can you suggest the ICs required?
    Thankyou.

    - - - Updated - - -

    I am designing the RF repeater for GSM band of frequencies i.e. uplink frequency range 933-960 MHz and downlink frequency range 890-915 MHz. Basically there will be a monopole antenna at the top of roof that will receive the signals and will transmit them through a coaxial cable. This coaxial cable will have its end attached to an amplifier and a band pass filter whose output will be given to another monopole antenna that will radiate the signal in the area having less network coverage. This arrangement was for receiving the signal, a similar arrangement is to be done for transmitting the signals back. So for designing these RF amplifiers and band pass filters can you suggest a suitable IC?
    Thankyou



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    Re: doubt on RF repeater IC's

    I'm not sure that is going to work. GSM is time division multiplexed with a co-ordinating channel that issues the time slots to stations in the vicinity. If you introduce delays it will stop working and by extending the range you risk more than one device 'grabbing' the same time slot. I think GSM repeaters have to be based on "store and forward" principles, basically, your repeater is seen as a mobile device from the first cell station and connects normally then passes the data packets to a second cell station to increase the range. I don't think analog signal boosters will work.

    I may be wrong, I was involved in the designing GSM base stations in the USA back in the 1980s but I haven't worked on it for many years.

    Brian.
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    Re: doubt on RF repeater IC's

    Yes i am also not sure whether it may work or not, i am just trying to put a simple idea into motion. so can you just suggest me ic's which are power amplifiers in range of 933-960 mhZ and 890- 915 MHz and band pass filter ics for the same frequency. i just want to try out on this simple idea but do not know what ic's i have to use



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    Re: doubt on RF repeater IC's

    GSM repeaters based on diplexers and selective amplifiers can be made and are commercially available.

    But you need considerably deeper knowledge of RF engineering than applying an amplifier IC to make it.



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    Re: doubt on RF repeater IC's




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