February 2008 -- In the next 12 months, there will be some technology changes across the United States that will affect many things we use in our daily life. These changes are occurring as a result of a coming shift to digital transmission systems and away from the analog systems that have been in use for several years.
Digital transmission systems differ from analog transmission systems in the way they encode the information being sent. Analog systems transmit their data using continuously varying signals, while digital systems first convert their data to a numerical form, and then transmit the data as a series of numbers.
Why shift to digital?
Though the digital transmission system is more complex than analog, it is vastly more efficient. In today’s world, more devices need to wirelessly transmit and receive information than ever before. Each device’s transmission uses up a frequency or frequency range of the available spectrum for its broadcast. As a result, the entire broadcast spectrum available is very crowded, and competition for slots in the spectrum is fierce. The FCC is planning to auction off a slice of the 700MHz band in January, and wireless providers like AT&T, Verizon, and even Google are preparing to bid billions of dollars to purchase that spectrum. The providers are planning to use the bandwidth for next-generation wireless services.
Since the available frequencies are so crowded, their use must be made more efficient in order to continue to expand and provide services. Digital transmissions can make much better use of the spectrum than analog transmissions can. In some cases, up to 16 times as much information can be transmitted using digital broadcasts instead of analog. Even more information can be transmitted using compression techniques, which are impossible to use on an analog signal.
A change in your TV viewing
A ruling by the Federal Communications Commission and a congressional bill are the two driving forces behind these major shifts in technology. In 2005, the U.S. Congress passed a bill requiring that all television broadcasters stop broadcasting the analog version of their TV channel on February 18, 2009. Also, in 2002, the FCC ruled that wireless telephone service providers no longer have to maintain their analog mobile phone networks beyond February 18, 2008.
Television broadcasters have been preparing for this shift for a while. Most television broadcasters currently are broadcasting the digital version of their signal alongside the analog version. The analog version of the signal is known as the NTSC signal, named after the 1940 National Television Standards Committee, which standardized the signal format. The digital version of the signal is known as ATSC, named for the Advanced Television Systems Committee, formed in 1982.
The item in a television that makes it a television (rather than a simpler monitor) is the tuner. This is the electronic section of the television that enables it to receive a broadcast signal. A monitor (like those used for a computer) has no tuner, and can only display something from a plugged-in cable. Until a few years ago, most televisions that were purchased contained a tuner that could receive and display only NTSC (analog) signals. Today, most TVs have a tuner that can receive ATSC (digital) and NTSC signals. In fact, many retailers have stopped selling TVs that have NTSC-only tuners.
The shift to digital-only broadcasting on February 18, 2009 affects you if you currently receive broadcast signals over the air (OTA), and have a TV that has an NTSC-only tuner. On February 18, 2009, NTSC signals will no longer be broadcast, so your NTSC-only TV will no longer be able to receive any signals.
It’s estimated that the change affects about 20 million TVs currently in use throughout the United States. This is actually a relatively low percentage of all the TVs out there - by some estimates only 5 percent to 10 percent.
Most TVs will remain unaffected because they don’t get their signal from an over-the-air broadcast. Instead, they are connected to a cable TV service, satellite TV service, or other service that uses some type of set-top converter box. All of these services are unaffected by the change in the broadcast standard, and will continue to receive service as they do now.
If you are affected by the change, there are several choices for you. Starting in early 2008, converter box devices will hit the market that are ATSC tuners. You will be able to purchase one of these devices and hook it up to your older, NTSC-only TV. The converter box will allow you to tune in the ATSC broadcasts, and it will convert the signal to NTSC to allow your TV to display it.
When the FCC and the U.S. Congress developed the bill to change to digital TV broadcasts, they did not forget that you shouldn’t have to pay for this converter box. Starting in early 2008, people who will be affected by the transition to digital TV broadcasts can apply for and receive two $40 vouchers good toward the purchase of the ATSC converter box.
Details of the voucher program are available on the US Government’s Digital TV Converter Program Web site at http://www.dtv2009.gov. The site has information about the transition to digital TV broadcasting, online and printable applications to receive the vouchers, and lists of authorized ATSC converters and participating retailers.
By the way, your tax dollars are not paying for the vouchers - the aforementioned sale of the 700MHz wireless spectrum is paying for them. The 700MHz wireless spectrum is being freed up by the transition to ATSC signals, because 700MHz is where NTSC UHF channels 52-69 are currently being broadcast, and will stop doing so on February 18, 2009.
One item that is not covered by the vouchers is a TV antenna. If you need to receive ATSC signals over-the-air, and you live in a rural or fringe area, you may need a different TV antenna than the one you’re using now. While NTSC signals can be received at the fringe of their broadcast range, and the low-quality picture might be tolerable, an ATSC signal will likely cut out completely. A larger antenna, mounted higher in respect to the surrounding land might be required to receive the signal at all.
Another potential solution is to upgrade to an ATSC-capable TV. Most TVs on the market now have a built-in ATSC tuner, and in general will display a better picture than TVs that are several years old. Unfortunately, the government voucher cannot be applied to a new TV.
A final possible solution is to sign up for service with a TV service provider, like cable TV, satellite TV, or other service that uses a set-top box. The set-top box will output NTSC signals compatible with the older TVs. This may not be possible if such services are not available in your area.
Changes for mobile phone networks
A second industry affected by the coming shift to digital transmission technologies is the wireless telephone industry. The FCC ruled that on February 18, 2008, wireless carriers may (at their discretion) begin to shut down their analog cellular service. The Advanced Mobile Phone System is what we know as the older, analog cell phone network that was first used commercially in the United States in 1983, complete with brick-sized and brick-heavy phones.
The three largest wireless carriers that still have AMPS service - Verizon, AT&T, and Alltel - have stated they will shut down most portions of their AMPS networks soon after the February 18 date. Many smaller providers, especially those that cater to rural areas, will continue to maintain their AMPS network for the foreseeable future.
One problem with the shutdown of the AMPS networks is coverage. The digital wireless telephone technologies do not cover as large of an area as the older analog network does. Though the FCC ruling prohibits the wireless carriers from shutting down AMPS in areas where sufficient digital coverage is not available, there are bound to be unforeseen gaps in coverage.
Though hardly anyone has an analog-only mobile phone anymore, there are still many tri-mode phones in service, which have the ability to place calls on both the digital networks as well as AMPS. These phones will, in many places, be unable to receive an AMPS signal and will have to rely on the digital networks. Since many of these phones are older, they tend to be less reliable on the digital networks than modern phones, and may not get complete coverage, even in urban areas.
For those very few people who have an AMPS-only or tri-mode phone, the answer is to probably visit your wireless provider and investigate an upgrade to a newer phone that is digital-network capable. Fortunately, this will affect very few wireless subscribers.
GM OnStarWhile the shutdown of AMPS service will not be a huge problem for the mobile phone industry, it presents a larger problem for certain embedded systems. One of the largest installed bases of embedded systems that will have trouble dealing with the shutdown of AMPS service is GM’s OnStar in-vehicle assistance and safety system. The OnStar system relies on a combination of vehicular sensors, GPS technology, and mobile phone service that until recently, was AMPS-only.
GM has posted a set of Frequently Asked Questions regarding the analog to digital transition and how it affects the OnStar service. The FAQ is available at http://www.onstar.com/us_english/jsp/customer_service/adt.jsp.
GM produced three different types of OnStar systems in their vehicles. The first was an analog-only OnStar system. This system was used on certain GM vehicles as late as 2004 models. This OnStar system is the one most heavily affected by the AMPS shutdown, as it will cease to function after February 18. GM offers no upgrade option for these vehicles.
The second system was an analog/digital-ready system. This system uses analog-only transmission also, and will also cease to function after February 18, but this system can be upgraded to use the digital wireless networks. GM is offering an upgrade for eligible vehicles for $15 when purchased with a one-year subscription to OnStar service.
The third system is an analog/digital system that is already equipped to work on either analog or digital wireless networks. This is the only system that will continue functioning after February 18 with no action required by the vehicle owner.
To check which type of OnStar system your GM car has, go to https://www.myonstar.com/adt.os and enter your vehicle’s VIN number. GM’s Web site will tell you what type of system you have and whether there is an available upgrade.
Even though many OnStar-equipped GM vehicles can either be modified to use the digital wireless networks or can already use them, the digital network coverage is not as comprehensive as the AMPS network. There may be areas of the country in which the OnStar system will not function because there is no digital network coverage. Go to http://www.onstar.com/us_english/jsp/coverage_map.jsp to view the analog coverage map, and http://www.onstar.com/us_english/jsp/coverage_map_2008.jsp to view the digital coverage map.
GM states in their press release that they didn’t move toward an analog/digital sooner because it was uncertain which digital wireless technology would dominate. There were at one time four different major digital wireless networks in existence: TDMA (used by AT&T), which is being phased out, CDMA (Verizon and Sprint), GSM (AllTel, T-Mobile, and now AT&T), and IDEN (NexTel), which is also being phased out. GM also states that until recently, digital network coverage didn’t approach the AMPS network and therefore didn’t make sense given OnStar’s goal of having service available everywhere.
OnStar-equipped vehicle owners should visit the GM Web site as soon as possible to verify the status of their vehicle and whether an upgrade is available. If you happen to be one of the unlucky owners whose OnStar system cannot be upgraded, there are unfortunately no options to make the OnStar system usable again. You can get some of the equivalent functionality in the vehicle by having a good digital wireless phone and a GPS unit, but many of the other OnStar services will not be available.
Alarm systems
The AMPS shutdown will also affect premises alarm systems, such as the home security systems provided by ADT, Brinks, and others. Many of these systems transmit their alarm signals to the central monitoring company via a land-based telephone line, but some use a cellular telephone network module as a backup to the land-based line or, in some cases, the cellular network module is used as the primary means of connecting to the monitoring center. Most of the existing cellular modules in the field today are AMPS-only, and will stop working after February 18.
While most of the large alarm companies like ADT and Brinks have been preparing for the shift, and now offer wireless modules that use the digital networks, many smaller alarm companies are unprepared, and may not even have an upgrade path. Further, some cellular modules were sold by several companies that were labeled "digital," even though they actually used a digital sub-channel of the AMPS network rather than actually communicating over the digital wireless networks.
If your home security system uses a cellular module, contact your alarm company and make sure it connects via the digital wireless networks. If not, see if you can upgrade the module to one that does. If neither option is available, you will need to see about hooking your security system up to a land-based telephone line. In some cases, the alarm companies will allow you to use a voice-over-IP telephone line for monitoring instead of a classic land-based telephone line.
Though the transition to digital broadcast technology is going to be rough in some instances, it is a necessary shift in technology. The continually growing demand for more services is driving the change to be more efficient about the use of the available broadcast spectrum. After these two major shifts occur to digital broadcast technology, the only major consumer broadcast that will continue to use analog technology is AM and FM radio. Though other analog broadcasts still exist, such as CB, aircraft communications and navigation, government communications, and emergency services, those too, in time, will shift to digital technologies.
Digital evolution will drive more changes
It’s also not going to be the last change. As technologies evolve, future transitions will become more frequent. It’s highly unlikely that today’s digital technologies will exist unchanged for time periods like the 24-year run for AMPS, or the unbelievable 69-year run for NTSC. The ever-present and growing demand for additional services will always be driving evolutions toward new technologies.
