Professional Pilot, October 2016

cation As a phone changes position the data source cycles between cellular antennas and Wi Fi providers if the device is configured appropriately with signal strength being a function of the ambient network capabilities and limitations Transitions are annunciated using symbols and abbreviations on the main screen Individual settings and preferences are very important when it comes to bandwidth Applications on smart phones and tablets typically update software automatically when they latch on to a Wi Fi signal If a Wi Fi source is unavailable the default is to switch to cellular If such option is enabled it can be expensive for those without unlimited data plans One urban legend says that when a manufacturer produces a new version of their phone they deliberately slow down earlier versions to secretly nudge consumers into purchasing the upgraded model Theres no proof to support that allegation but its possible that language within a cellular contract may indicate a transmission rate slowdown once a certain amount of bandwidth has been consumed Universally transmission rate standards are determined and published by the International Telecommunication Union ITO an agency of the United Nations that consists of 193 countries and hundreds of private entities and academic institutions The current apex of the scale established in March 2008 is known as 4G or 4th generation From a technical standpoint a mobile 4G device needs to peak at 100 megabits per second Mbps or in more practical terms enough to stream movies and video For comparison a 3G network 92 PROFESSIONAL PILOT October 2016 can handle music and video albeit noticeably slower than 4G and a 2G is limited to phone calls text messaging and very limited data All of the major providers continue to operate 2G networks but 1 announced it would end that service in January 2017 effectively making subscribers whose devices are capable of only 2G essentially worthless Those 3G or 4G phones that display EDGE or GPRS on the screen are operating on a 2G network which severely restricts the devices capabilities Its worth noting that if the term LTE Long Term Evolution appears next to the 4G symbol it describes a methodology rather than a rate analogous to NextGen in aviation Critics describe 4G LTE as a bit of a marketing ploy because when the standard was established by the ITU no devices on the market could achieve the maximum rate As a result the term 4G was allowed if anything better than 3G could be achieved Its like calling something broadband How fast is broadband No one knows for sure because its defined as anything faster than dial up Popular psychology says the number of bars or dots depicted would be a good indicator of signal strength and consequently the speed But thats not true because different phones use different algorithms to compute display parameters The underlying metric for signal strength is dBm or decibel per milliwatts a logarithmic scale Its a little known fact among users but the actual dBm number can be determined by accessing the field test menu for the phone Users of the iPhone Satcom Direct Router SDR uses a satellite or a 3G connection to ensure uninterrupted data and voice connectivity in all phases of flight Aerowave 100 Wi Fi router is an affordable solution for turboprops and very light jets This router can be configured for both voice and data or for data only connections