Re: Emulating a wireless access point

From: David Ford (davidat_private)
Date: Wed Aug 15 2001 - 15:21:37 PDT

  • Next message: César González: "cmdasp.asp & unicode"

    This is perfectly true with the caveat that for every harmonic that you 
    step away from the prime, the power of the transmission drops 
    proportionately.  This is all considering there is no harmonic 
    filtering, also known as a bandpass filter.
    
    Here is where you truely get what you pay for.  Inexpensive equipment 
    tends to skim on features such as noise suppression and filtering.  Such 
    manufacturers don't care very much if they are splattering noise across 
    the spectrum.
    
    David
    
    bparisat_private wrote:
    
    >	You are correct Meredith.
    >
    >	I live near a cell tower (100m away) and can clearly hear cell
    >conversations on my scanner at the 1st lower harmonic, app 450-460Mhz.
    >
    >	Getting back the the original question, cordless 2.4Ghz phones are
    >notorious for creating interference with other devices using the same freq
    >band. I recommend not operating 2.4Ghz phones in a wireless environment.
    >
    >William S. Paris
    >Telecommunication/Network Analyst
    >Sorrento Lactalis Inc.
    >bparisat_private
    >
    >
    >	Actually, it probably has to do w/ the frequency / harmonic
    >resonance of
    >the phone interfearing w/the AP ... not the proximity. Even if the phone
    >operates on a different frequency, it can interfere w/ the AP via harmonic
    >resonance.
    >	Harmonic Resonance occurs when one of the frequencies is a multiple
    >of the
    >other. Say your AP operates at 2 hz ( for simplicity sake) and your phone
    >operates at 4 hz, then every other cycle of the phones frequency will be in
    >phase w/ the access points.
    >
    >ASCII Diagra:
    >|                  x -- sine peak                 As you can see, the sine
    >waves are prefectly
    >|      |   |   |   |                Phone         in-phase at 2 and 4 w/
    >respect to the phone.
    >|     | | | | | | | |
    >|        |   |   |   |
    >|_________________________________ T = 1 sec
    >|
    >|    	  	       x -- sine peak
    >|          |       |
    >|     ....| |.....| |.               Access Point
    >|             | |
    >|              |
    >__________________________________ T = 1 sec
    >
    >	Are there any Ham operators out there that can confirm or deny this?
    >
    > -- Meredith Shaebanyan
    >
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