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  1. #21  
    Quote Originally Posted by KStewart View Post
    Great analogy. I never looked at it that way, and now that I do I am scratching my head as to the higher frequency wall penetration problem with Sprint. Sprint is natorious for dropping calls or getting week signal in buildings. Me and my wifes phone drop calls off and on in Target. Target and Wallmart seem the worse out of the places we shop with Sprint. If higher frequencies have better penatration...whats going on with Sprints all 1900MHz network? I drop calls like crazy in the basement with my 700p, but as soon as I force roaming on to Verizon's network at 800MHz I get a strong singal that I can hold a long conversation with. If you look at your insite and Sprints performance test they contradict each other, unless there is a missing variable? With propagation being a factor...do you have to build a tower right outside of target in the parking lot to get penatration?
    That higher frequencies contain more energy, and thus have better penetration is theoretical, and dependent on all other things being equal. Sprint's towers may have lower transmission wattage, and/or be further away to a customer's handset (SAR is for handsets, not sure how towers' RF energy is quantified)? With respect to Target and Walmart specifically, perhaps the large prevalance of flourescent lights are creating some sort of interfering EMF?
  2. #22  
    Quote Originally Posted by cinealta View Post
    That higher frequencies contain more energy, and thus have better penetration is theoretical, and dependent on all other things being equal. Sprint's towers may have lower transmission wattage, and/or be further away to a customer's handset (SAR is for handsets, not sure how towers' RF energy is quantified)? With respect to Target and Walmart specifically, perhaps the large prevalance of flourescent lights are creating some sort of interfering EMF?
    Unfortunately, that's exactly the opposite... higher frequency suffer larger dispersions and the higher is the frequency, the larger are the loss when crossing obstacles...
    850MHz (900 in EU) are indeed preferred to cover open spaces (e.g. highways in the countries) and to offer better inside coverage.
    Think about FM or AM radios... one tower allow easily you to cover hundreds of km...
  3. #23  
    Quote Originally Posted by fasuin View Post
    Unfortunately, that's exactly the opposite... higher frequency suffer larger dispersions and the higher is the frequency, the larger are the loss when crossing obstacles...
    850MHz (900 in EU) are indeed preferred to cover open spaces (e.g. highways in the countries) and to offer better inside coverage.
    Think about FM or AM radios... one tower allow easily you to cover hundreds of km...
    Sorry, I respectfully disagree. FM radio is on the order of 88-106 MHz. That's a factor of 10x less frequency than 850 MHz cellular transmissions. Shortwave radio (which can be heard around the world, discounting ionospheric bounce) is 10x less than FM. AM radio is in Kilohertz. A factor of 1000x less frequency (cycles/second) than FM radio.

    The lower the frequency, the further a wave travels, but because it has less energy (lower frequency), the more easily it is dispersed (eg by concrete).

    According to Einstein, the energy of a wave is proportional to its frequency (E=hf, where h is Planck's constant). Think about, Gamma rays penetrate through anything, including lead, steel, titanium etc and their frequency is extremely high.
    Last edited by cinealta; 07/25/2007 at 01:36 AM.
  4. #24  
    Quote Originally Posted by cinealta View Post
    Sorry, I respectfully disagree. FM radio is on the order of 88-106 MHz. That's a factor of 10x less frequency than 850 MHz cellular transmissions. Shortwave radio (which can be heard around the world, discounting ionospheric bounce) is 10x less than FM. AM radio is in Kilohertz. A factor of 1000x less frequency (cycles/second) than FM radio.

    The lower the frequency, the further a wave travels, but because it has less energy (lower frequency), the more easily it is dispersed (eg by concrete).

    According to Einstein, the energy of a wave is proportional to its frequency (E=hf, where h is Planck's constant). Think about, Gamma rays penetrate through anything, including lead, steel, titanium etc and their frequency is extremely high.
    Ouch...Impressive 3 posts, welcome to T/C
    at&t iPhone3G
  5. #25  
    Quote Originally Posted by KStewart View Post
    Ouch...Impressive 3 posts, welcome to T/C
    Thanks. Great to be here. Long time Palm user and reader of this excellent site.
  6. #26  
    After using EVDO, I can never go back to EDGE like speeds.
  7. #27  
    Quote Originally Posted by cinealta View Post
    Sorry, I respectfully disagree. FM radio is on the order of 88-106 MHz. That's a factor of 10x less frequency than 850 MHz cellular transmissions. Shortwave radio (which can be heard around the world, discounting ionospheric bounce) is 10x less than FM. AM radio is in Kilohertz. A factor of 1000x less frequency (cycles/second) than FM radio.

    The lower the frequency, the further a wave travels, but because it has less energy (lower frequency), the more easily it is dispersed (eg by concrete).

    According to Einstein, the energy of a wave is proportional to its frequency (E=hf, where h is Planck's constant). Think about, Gamma rays penetrate through anything, including lead, steel, titanium etc and their frequency is extremely high.
    That's what I was saying... the lower the frequency is, the longer they get...
    When considering GHz range (1800MHz or 1900MHz where once called microwaves...) the problem is with Rayleigh fading, reflections, etc... Those effects can be neglected when the wavelenght is large (i.e., the frequency is low). But the higher the frequency is, the larger are those effects...

    At least that's what I remember from my past courses.
  8. #28  
    There are many ways to cut the 'faster' cake. I travel a lot so I have TMO for hotspots at every airport. I have a Dash so (for example) here I sit at SFO using -- wait for it -- wifi.

    For email and such EDGE is fine. I had Sprint's EVDO for a while and . . . . meh. No big deal. Wifi does make a difference for me though.
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