A Satellite Phone Primer - Radio World

A Satellite Phone Primer

As international events continue to have more impact on us in the United States, and weather or other natural disasters seem to be more commonplace, the need to pick up and go anywhere on a moment's notice for a live broadcast is becoming more pressing. Enter the satellite phone.
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Even with the many technological advances in remote gear, there are still limitations relating to how most stations can cover off-site happenings.

If a remote location is far from a 450 MHz STL receive site or telephone line, it may be considered out of reach. As international events continue to have more impact on us in the United States, and weather or other natural disasters seem to be more commonplace, the need to pick up and go anywhere on a moment's notice for a live broadcast is becoming more pressing.

Enter the satellite phone.

Range of services

Even though sat phones have been around for about 10 years and are used by many networks, they often are considered too esoteric or expensive for the average radio station. The satphone landscape is changing quickly, however, as hardware costs are falling, new services are coming online and providers are gearing up with turnkey services to government agencies, relief workers and radio broadcasters.

Several options are available for satellite phone service, ranging from simple to elaborate.
High-Tech CuteAnywhere, anytime satellite radio remotes are a reality in Cologne, Germany, where broadcaster WDR is using a Mercedes mini-Benz crammed with high-tech gear, as reported in the German magazine Cut.

The tiny car is a self-contained broadcast unit, including wireless microphone and headphone, mixing console, ISDN codec and satellite gear. All of the equipment is contained in a 19-inch rack located under the rear hatch of the car. The package was custom-designed by Trans Tel Communications of Hamburg.

On the roof of the mini-Benz is a satellite dish, which utilizes GPS, an inclination sensor and compass to calculate the position of the highest Inmarsat satellite and lock on to it. The dish is mounted on a VPT-41 pan-tilt head from Videor Technical which is directed to the bird by custom software developed by Trans Tel. A "ready" indicator on the dash lights up when the dish is correctly aligned.

The satellite connection can be established via a hand-held remote control, so the reporter does not need to return to the vehicle once an interview has begun. The remote satellite control works in a radius of 60 to 200 meters from the car.

An ISDN codec stores the telephone numbers and settings for 24 studio connects. Reports filed via POTS lines and with poor audio quality are virtually a thing of the past, as the mini-Benz is dispatched to those events where it would not be worthwhile to send a large remote truck.

The mini-Benz vehicle has been an unqualified success with reporters in Cologne, and WDR is ordering five more of the vehicles for regional studios in North Rhine-Westphalia.
At the most basic level are handheld sat phones, which resemble oversized cell phones. Most of these are good for keeping in touch from remote locations, but only provide voice-grade connections, so their use for on-air applications is not recommended.

There are a variety of satellite networks to choose from, depending on your needs. Iridium provides global coverage, including open oceans and the polar regions, with hardware costing around $1,500 and airtime costing about $1.50 per minute and a $28 monthly fee.

Other satphone networks are regional, and therefore cost less. For operations in the Middle East, Africa or Asia, Thuraya is an attractive option, with equipment costing around $800 and airtime of less than $1/minute and a $20 monthly fee. ACeS (Asian Cellular Satellite) covers India, Pakistan and most of most of the Asia Pacific region. International calls cost around $1 per minute.

GlobalStar's handhelds provide coverage of the Americas, Europe and the Middle East. Monthly fees start at $39.95, and there is a flat rate of $1.39/minute for calls between the United States and Iraq.

Next generation

At the next level are satellite modems, also known as mobile ISDN, or GAN (Global Area Network). The unit is the size of a small briefcase and provides both voice and data connectivity. Satellite modems allow users to access the Internet via the Inmarsat satellite system with a 64 kbps connection to send and receive e-mail, data files, media files, video tele-conferencing, faxes and voice messages from one compact unit. Inmarsat provides global coverage, except for the poles.

Hardware costs for the portable Inmarsat satmodem are around $8,000, with airtime costing about $2 per minute for voice, or $6 per minute for mobile, ISDN or data, or $4 per minute for MPDS or data. Mobile tracking antennas are available as an option, enabling satellite modem operation for mobile or maritime operations, even while the vehicle is in motion.

The next step up from satellite modems are vehicular satellite, or VSAT systems. They are packaged in two "airline checkable" flight cases, and offer up to T1 (1.54 Mbps) speeds. Many of the VSAT systems have auto-acquiring antennas, which work in conjunction with the system's GPS receiver to locate and lock on to the satellite signal automatically. These systems operate in the Ku-band and are marketed at IP-based mobile office/studio applications.

Up until now, most broadcast use of satphone technology has been at the network level. John Stoltz, business development manager-media for GCS (Global Communications Solutions), said that could all change over the coming months.

"In 2005, the next generation of satellite modems from Inmarsat will be available. BGAN - Broadband Global Area Network - will offer DSL-like (up to 432 kbps) bandwidth speeds from a laptop-sized satellite modem costing less than $3,000."

Stoltz said voice, legacy ISDN and IP services will be available in addition to a dedicated "streaming" class service.

"Due to the lower hardware and service costs, backpack news gathering will now be more affordable and easier to use, even domestically. Users just have to plug the laptop satellite modem into an IP-based audio codec for a complete system." Stoltz estimates that this next generation of hardware will open up the satphone market to affiliates and radio freelancers.

Satphones and associated gear also can be rented from a service provider on a daily, weekly or monthly basis. Stoltz said, however, that if users plan on renting for four or more months, it is usually cheaper to purchase a unit outright.

Line of sight

As promising as satellite phone technology is, there are limitations and precautions.

Satphones only work outdoors where there is line of sight to the satellite, making operations in urban areas or around airports problematic. Communications may not always be secure, as hackers with bootleg satellite receivers and DTMF decoders can listen in, and learn a caller's identity by decoding the phone number and tracing it back.

Low earth orbit satellite systems such as Iridium must frequently hand off calls from one satellite to the next. During these transitions, audio glitches can occur and calls occasionally are disconnected.
Satphone Service ProvidersGlobal Communications Systems Chicago (773) 248-8686 www.globalcoms.com

Global Com Satellite Communications Decatur, Ill. (888) 636-0707 www.globalcomsatphone.com

Applied Satellite Technology United Kingdom 011-44-1493-440011 www.satcomms.com

Trans Tel Communications GmbH Germany011-49-40-697078-0
Availability issues need to be understood, said Gerald List, managing director for Trans Tel.

"The Thuraya handheld satphones were banned by the U.S. forces during the Iraq war, owing to a fear that the user's position might be forwarded to the enemy. Maritime Inmarsat satellite systems give priority to distress calls and will terminate other calls if no free channels are available."

List said savvy users can circumvent some of these problems by registering with several or all land earth stations to have different options available.

Satphone providers seem able to handle excess capacity of calls with little difficulty.

"Shortly before the Iraq war began," List said, "Inmarsat activated a spare satellite to cover Iraq with an additional spot beam. Television customers of Inmarsat used this new satellite to transmit live and store-and-forward video, whilst others had difficulty getting through."

Most saphones operate in the L-band, and are relatively immune to weather-related service disruptions. There may, however, be occasional disruptions of service during solar storms.

Overseas users need to be aware of restrictions and embargoes in certain areas. For example, in restricted countries including North Sri Lanka, North Korea, Poland and Hungary, Iridium phones will not complete a call to the local phone system.

While satphones will work in embargoed countries including Cuba, Iran, Libya, Sudan, Afghanistan, Angola and Yugoslavia, phones may be confiscated by customs officials. Broadcasters must obtain prior permission from the government before bringing satellite gear across the border.

Finally, while satphones are becoming more affordable and easier to use, this is not yet a plug-and-play technology. Novice users would do well to deal with one of the turnkey service providers who has had experience with broadcasters, rather than a box warehouse on the Internet.

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