rwzeitgeist

The Short Message Service (SMS) is defined to send a single short message in a single packet. Coding the characters in 7 bits rather than 8 allows the message to contain 160 characters in a 128 byte packet payload. The SMS packets are not sequenced. The protocol definition does not require packets be delivered in the same sequence as the messages were sent. If you are familiar with TCP/IP you should think of SMS packets as equilavent to UDP packets, without the ordering guarantee required by TCP. I can readily imagine that given an unordered collection of packets addressed to the same destination the various servers process each packet on any of several threads. Thread scheduling leads to the possibility that the packets, which you think of as sequenced, are processed out of sequence. The more servers a collection of messages passes through the more likely the sequence gets scrambled. Server load is probably the largest variable that results in delivery delays. SMS, like UDP, is a "best effort" service. You will find no carrier offers even Fortune 50 corporations a delivery time guarantee, or even a guarantee that a message will ever be delivered. I know of multiple companies using SMS for process control problem alerts ("tank 5 is about to overflow") that want to switch to a different technology because of poor SMS performance where both sender and receiver are in the same state and on the same carrier. Most of the time a collection of related SMS messages happens to arrive both promptly and in the same sequence as they were sent. However, you cannot assume that the behavior you usually experience is defined as the correct behavior. Bob

The Sensorly maps show Sprint LTE coverage in that area, although not as strong as any of us would want. You would probably get an LTE connection outside, but from inside a building a device would most likely switch to 3G. The above was my situation at my office near 121 & the Tollway until about a week ago Sprint turned on a brand new tower near that intersection. The sponsor area contains separate a maps that show Sprint tower sites regardless of upgrade status, and another map showing what changed at each upgraded tower site. Bob

I assume you don't get an LTE signal inside your home or office. A quick trip in the car might be shorter than the interval between your device's searches for LTE service, resulting in no search for LTE service during a quick drive to work. When you get into your vehicle, try cycling airplane mode, which will force the device to look for LTE service. I do that when I run Sensorly to map a service area, and the phone will find LTE when airplane mode goes off where it wasn't using LTE when I entered airplane mode.

You need all four lights showing solid green. A red blinking light means the unit is unhappy about something. The one in my home improves signal strength in about half the house. The unit ended up in my wife's office because that's where she usually uses her phone. I tried positioning the unit in the center of the house, but that location resulted in poor signal strength in the two locations we wanted improvement. (My office lost the battle. Through four walls and maybe 40 feet I get around -100 db.) I positioned the GPS receiver in the window so it would get a decent view of the sky. The unit needs a few minutes after powering up before all four lights turn green. Bob

I have noted a couple of times, since my EVO LTE's upgrade, that the phone holds an LTE connection in places where it used to lose it. Of course that result might or might not be because of the upgrade, and the incident frequency hasn't been high enough in enough different places to draw conclusions. I was hoping Sensorly would have enough data in some geographic locations to make comparisons at least interesting data points, if not definitive. Bob

A number of threads here and elsewhere discuss the relative strenghs/weaknesses of various devices' radios. Most of these discussions lack hard numbers to back up the assertions. Perhaps the data acquired by Sensorly could provide the empirical data to compare pairs of devices, or to compare a single device against the "average" device's radio performance. For example, there has been some discussion that the HTC EVO 4G LTE phone's LTE radio doesn't perform as well as some other devices. An extended query on the coverage map could overlay, for a particular radio such as the LTE radio, the coverage reported by the HTC EVO 4G LTE with the coverage reported by the Samsung Galaxy S III. I expect that when viewing the overlay at a high zoom level (lots of detail), one of the devices will show either a larger coverage area or a stronger signal in the same coverage area. Another interesting metric would be something along the lines of average signal strength per unit of coverage area for various devices for a specific radio. I expect a better radio will show a better average signal strength than a weaker radio. This metric would obviously require a fair amount of computation, but because the results won't change often the computation could be run as needed. Perhaps such a report could goad certain cellular companies into fixing problems with a device's radio that aren't obvious without munching a lot more data than is available to an individual? Bob

For a realistic look at coverage you should check out the maps on the Sensorly Web site, with an understanding that the crowd doesn't blanket the coverage area. My experience in the Plano/Allen/Frisco area suggests coverage remains spotty. I consider the growth of LTE sites since this market went live quite disappointing. During my 9 mile commute I see an LTE connection less than 50% of the time. Absolutely! At some locations between home and office the Speedtest app reports more than 20MB/sec, so when the phone, an HTC EVO LTE, finds a strong LTE signal the performance is amazing!

I see a tower scheduled for August about a mile from my office in Hall Office Park. The tower is at 3966 Parkwood Blvd, a bit Northeast of Parkwood & Gaylord. A tower in Plano a mile or so from my house is also scheduled for August. Soon!!! I flew into and out of San Antonio over the weekend. Several times I briefly saw an LTE connection while inside the airport, but the EVO LTE wouldn't hold onto it. Driving 410 between the airport and US 90, then West on 90 I noted what appeared to be LTE connections to more than one tower. Unfortunately I couldn't stop to investigate. While having a piece of pie at Marie Callendar's I unfortunately remained stuck with a 3G connection. But the pie was good! Bob

The most recent map of completed NV towers lacks coverage shows no entries for northern suburbs such as Plano, Frisco, The Colony, Carrollton, and Lewisville. Two towers in Richardson show up, and about an hour ago I established a 4G LTE connection to the one just north of UTD. Then there's one isolated completed tower just South of 380 on Preston Road. The Ft. Worth area shows a lot more completed towers than the Dallas area. Bob