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WiWavelength

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Posts posted by WiWavelength

    Mystery "Flagship" Phone coming soon!!!!

    in Misc.

    Posted

    Especially given all the recent cannibal news, not sire what to think of all this.

    Ok, I'm not that way! Gross!

     

    No, that settles it. Josh is a radioactive zombie cannibal. The whole vegetarianism and borrowed thumb were just to throw us off the trail.

     

    AJ

    I'll say it, Wimax was a good decision.

    in WiMax

    Posted

    I don't think that chart is accurate. It shows that propagation distance is inversely linear with frequency. From what I remember from my communication courses Loss = (c/(4*pi*f*d)^2. Signal loss is inversely proportional to the square of the frequency. Am I missing something or are the Verizon people wrong?

     

    Free space path loss (which is not really an ideal metric in this real world scenario, but it can still serve as a general measuring stick) increases by 6 dB for every doubling of frequency (i.e. halving of wavelength) or doubling of distance.

     

    I empirically derived a quick way to calculate the free space path loss difference (in dB) between two frequencies. Use this formula: 20[log(F₁/F₂)]. To illustrate, 20[log(1900/850)] = 6.99 dB, as PCS 1900 MHz experiences ~7 dB greater free space path loss than does Cellular 850 MHz.

     

    As for the VZW numbers referenced above, they are basically spot on. They use 2500 MHz as the baseline and calculate a ratio from there. For example, 2500/700 = 3.57, which jives with VZW's 3.5x ratio. Furthermore, plug the ratio into my formula to get the free space path loss difference then in dB: 20[log(3.57)] = 11.06 dB.

     

    AJ

    • Like 2

    Screen Protectors (Updated)

    in Misc.

    Posted

    $3 plus postage.

     

    Okay, I want to buy 1000. I will send you a money order for $5000. You keep $3000, then send me back the extra $2000 along with the screen protectors. Oh, and I need you to ship them to me here in Nigeria.

     

    AJ

    • Like 3

    Service Update

    in General Topics

    Posted

    By the way...they are using 310-FFF.

     

    In hex, FFF is 4095, which in binary is the largest 12 bit number. I presume then that the MNC must be a 12 bit value. So, while 310 (as well as 311-316) is the MCC for the US, Sprint appears to be using a null MNC value (much like 65535 is a null NID value).

     

    AJ

    Dallas LTE network live?

    in Markets

    Posted

    I sure wish my uncle would go get a job at sprint

     

    Hey, then maybe you, too, could be cool and run LTE speed tests before anyone else like PLANETEARTH aka TheComputerMaster, whose "uncle" works for Sprint.

     

    AJ

    • Like 1

    4G in crowded areas

    in Network, Network Vision/LTE Deployment

    Posted

    Yes and no. For at least the first few months, LTE everywhere will be like a wide open highway with no posted speed limit because only a small minority of subs will have LTE capable devices. Seven years ago, EV-DO was the same way for a year or longer.

     

    However, after LTE adoption becomes relatively commonplace, the sold out stadium paradigm will cause problems again, as it nearly aways does. One solution is aggressive use of DAS (Distributed Antenna System). But many venues limit DAS to one sponsor carrier, so that solution cannot be applied everywhere.

     

    The other solution is to throw ungodly amounts of spectrum at the problem. This is the solution that the wireless carriers -- especially VZW and AT&T -- want to implement, as it would help them gain control over literally hundreds of megahertz of licensed bandwidth per carrier. But that would be a gross misuse of spectrum as a public resource. It would be somewhat akin to overbuilding 20 lane highways to accommodate hurricane evacuation that happens once every few years.

     

    AJ

    Service Update

    in General Topics

    Posted

    Well, so far, I have had no luck with custom PRL swaps on the EVO LTE. PRL swapping on the handset requires the EPST.apk. But only certain versions of the EPST.apk allow access to the PRL dialer code (##PRL#). For example, I had to replace the stock EPST.apk on my EVO 4G with an older version before I could swap PRLs.

     

    I can report that the stock EPST.apk on the EVO LTE does not grant access via the PRL dialer code. My EVO LTE is rooted, so I used Root Explorer to replace the stock EPST.apk with the much older version that enabled PRL swaps on the EVO 4G. Unfortunately, it does not work with Android 4.0 or Sense 4.0 or both. In fact, the old EPST.apk not only does not grant access via the PRL dialer code but also removes access via the programming dialer codes (##DATA# and ##xxxxxx#, in which "xxxxxx" is your six digit MSL). So, the very old EPST.apk that allowed PRL swaps on the EVO 4G appears to be a dead end with the EVO LTE.

     

    Back to the drawing board...

     

    AJ

    • Like 1

    Service Update

    in General Topics

    Posted

    I looked at PRL 25003 and I can't find a one bit of the G block listed in there. Apparently the PRLs in these phones are for the CDMA side only. I haven't had a chance to snag 25004 yet, but I suspect it is the same.

     

    Correct, you will not find any PRL entries pointing to the PCS G block, since the PCS G will be solely LTE 1900. The same is true with WiMAX -- nothing in the PRL. Only AMPS, TDMA, and CDMA modes use PRLs. GSM and W-CDMA devices do not contain PRLs nor anything quite like lists of SIDs, NIDs, and channels. Rather, they use LACs (Location Area Codes), which are stored on the network side, not on the device side. Now, unlike the GSM zealots, I do not consider LTE to be GSM; LTE is a new paradigm for both GSM and CDMA operators alike. Regardless, LTE will not use PRLs. It may, like GSM, use network side LACs. Or LTE may use something else altogether -- maybe even IP or MAC address based roaming control.

     

    AJ

    Service Update

    in General Topics

    Posted

    Correct. I was talking about the prl for CDMA.

     

    Yes, that would be the only PRL, since LTE (and GSM and W-CDMA) do not use PRL based roaming controls. But my admittedly anecdotal understanding is that the CDMA/EV-DO PRL is now sequestered away on the SIM.

     

    AJ

    Service Update

    in General Topics

    Posted

    On another note, I am so happy that roam control works great on the EVO LTE. Time to do some prl playing.

     

    Reportedly, the PRL is now stored on the SIM and is impervious to tinkering. If that is not the case, do enlighten us.

     

    AJ

    Voice and Data on 3G

    in Network, Network Vision/LTE Deployment

    Posted

    SVDO capability is a side effect of other design requirements for the phones. The LG Viper LTE and EVO 4G LTE both require a dual-SOC design...

     

    No, that is no longer accurate.

     

    The Viper and previous VZW handsets that support SVDO can do so because they utilize dual Qualcomm modems, typically one MSM paired with one MDM. Typically, the MDM chipset is used for LTE connectivity; however, since the MDM is also EV-DO capable, it opens up SVDO capability.

     

    With the arrival of the Qualcomm MSM8960 (and other S4 chipsets), on the other hand, the EVO 4G LTE utilizes a single chipset that supports CDMA1X, EV-DO, and LTE, plus SVDO or SVLTE.

     

    AJ

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