The global research programme, commissioned by Inmarsat, was conducted over a two-month period in 16 locations around the world by TelAstra, Inc., an international telecommunications consultancy with extensive experience of satellite communications. They undertook a fully-independent comparison study of the three satellite phones using the six published claims made by Inmarsat for IsatPhone Pro: global coverage; robust handset; clear voice quality; reliable network connection; long battery life; and ease of use.
“All the satphones have pluses and minuses, and all of them would be acceptable with various limitations,” said Roger Rusch, TelAstra, Inc. “But unquestionably, IsatPhone Pro is the best. It works everywhere and is the most rugged. The voice quality is excellent, it has a reliable network connection, and the longest battery life of the three satphones. It is also easy to use.
“Although we were not asked to compare the price of the satphones or satphone services, it appears that IsatPhone Pro prices are significantly less expensive, and the service rates appear to be highly competitive as well. IsatPhone Pro would be our choice regardless of affordability or any other single issue,” he said.
The comprehensive Satphone Comparison Study from TelAstra, Inc. provides extensive data on the user experiences of two researchers and their conclusions.
TelAstra, Inc. verified the global coverage of IsatPhone Pro, with consistent performance in all 16 locations, from Anchorage to Zimbabwe. The study also acknowledged the global coverage provided by Iridium, although it noted frequent connection denials and disconnections. No claims of global service are made for Thuraya XT.
In mechanical drop tests to measure the robustness of the three handsets, IsatPhone Pro led the group; the only effect of half-metre and metre drops was a loose battery cover, which was easily put back in place before successfully making a call. The Thuraya XT experienced a damaged antenna, while the Iridium 9555 suffered the most extreme damage, with a cracked case and broken antenna, and was not functional after the drop tests.
Voice quality on IsatPhone Pro was frequently reported as clear and “better than cellular”. The Iridium 9555 provided similar voice quality under the best conditions, but the study found that it sometimes offered “terrible call quality”. The researchers reported Thuraya XT’s voice quality as slightly inferior to the other two handsets even in the best conditions, although not significant enough to be a factor.
The study found that the IsatPhone Pro took between 72 to 120 seconds to obtain an GPS fix and make a call. For subsequent calls, and without the need to get another GPS fix, IsatPhone Pro was ready for calls within 10 to 34 seconds. Thuraya XT also acquired very quickly, the study found.
The study found that the Iridium 9555 was ready for dialling within 31 to 40 seconds. However, while the availability of IsatPhone Pro and Thuraya XT was essentially 100% during the entire testing programme, the researchers had to wait for between 5 and 12 minutes to connect to the Iridium network on several occasions.
Similarly, while IsatPhone Pro and Thuraya XT offered reliable connections, the researchers experienced frequent dropped calls with the Iridium 9555. They conclude that “it seems impossible to have an extended call on Iridium 9555 without interruption… Our experience was that most of the time the Iridium service is hit or miss”.
In comparison, TelAstra, Inc. found IsatPhone Pro to be “remarkably stable”. The researchers commented in the report: “We routinely talked while walking around Palos Verdes, Los Angeles, for 20 minutes or more. We had two 1.5-hour and one 2.5-hour uninterrupted stationary calls during the battery capacity tests”.
Tests on the battery life of the three handsets showed that IsatPhone Pro had the longest talk time and stand-by time, with measured talk time of 7 hours 45 minutes (against a published claim of 8 hours) and measured stand-by time of 84 hours (against a published claim of 100 hours). This compared to a talk time of 5 hours 6 minutes, and stand-by time of 30 hours, for the Iridium 9555; and talk time of 6 hours 19 minutes, and stand-by time of 38 hours 30 minutes, for the Thuraya XT.
The study looked at a range of areas to assess the phones’ ease of use. It found that, while the keypads of IsatPhone Pro and Iridium 9555 were large enough to use while wearing gloves – essential in certain environments – the smaller keypad of the Thuraya XT was more likely to cause input errors. The researchers found that all screens were difficult to read in bright sunlight; in dim light, the monochrome screen of the Iridium 9555 was the hardest to read. The study found that all handsets were convenient to hold while talking or walking.
“We know that satellite phone users apply these six criteria when judging a service, which is why we designed IsatPhone Pro to perform well in these areas,” said Drew Brandy, Director of Land Business at Inmarsat. “We were highly confident that we were offering the market leading service, but the hard facts of this independent study now confirm it. This is an extensive piece of research, conducted globally, and it validates all of our claims.”
A video interview with Roger Rusch, detailing the research programme and explaining the findings, is available at YouTube.
The Satphone Comparison Study report can be downloaded from the Inmarsat web site.