Test Finds U.S. 4G Networks Work as Advertised

U.S. mobile service providers in a number of U.S. cities provide fourth generation network service to users in moving vehicles “as expected and advertised,” a new study by Signals Research has found.

You might argue that the study provides both “good news” and “bad news.” The “good news” is that service provider claims about performance generally are validated. The “bad news” is that the incessant positioning of networks as “fastest” or “best” are not validated.

Performance will vary from site to site, not to mention city by city, but also by device and components within devices. The good news for consumers is that network quality might not be a big issue, though coverage could be a more-important factor.

Consumers are not generally going to be able to determine, in advance, now much the specific devices they wish to use will perform on a given network, though.

The study also found that latency is an area where all the networks could show meaningful improvement, though just 40 milliseconds of latency separates the best performing network from the “worst.”

The lowest latency (27 ms) was observed on T-Mobile USA’s network.

But not all of the performance is a function of the networks. As it turns out, chipsets and devices also impose performance limitations.

“Once normalized for channel bandwidth and MIMO, not to mention taking into consideration network loading, the performance differences across all technologies were relatively modest in the downlink,” Signals Research says.

In a few cases, DC-HSDPA (such as used by T-Mobile USA, outperformed Long Term Evolution. Also, in some cases EV-DO Rev A (as used by Sprint and Verizon Wireless, for example) outperformed HSPA+ (used by AT&T, for example).

But uplink throughput is an area where LTE generally has a big advantage over its peers, the tests suggest.

Tests were conducted in Phoenix, Dallas, Kansas City, San Francisco, San Jose, Oakland, Myrtle Beach, SC, Charleston, SC, and Houston.

Operators in the study included AT&T (HSPA+ and LTE), Clearwire (LTE 2x20MHz and Mobile WiMAX), T-Mobile USA (DC-HSDPA and HSPA+), and Verizon Wireless (EV-DO Rev A and LTE).