Satellite TV for trucks

Typically a satellite truck will have its own on-board power source such as an electrical generator or inverter to create the alternating current to power all the transmission systems, which makes it a true independent mobile satellite transmission entity. Often such trucks also have various degrees of video production equipment and video editing gear. This equipment allows these trucks to also act as mobile electronic news gathering (ENG) facilities, or they can even be outfitted to do an electronic field production (EFP) to create an entire television show with multiple switched professional video cameras, character generators (CG) for digital on-screen graphics, video tape recorders (VTR) and video servers.

Most satellite trucks have typically been built on a light or mid-duty truck chassis with 6 wheels; usually with 4 tires on the rear axle. All the equipment is mounted into the truck in racks that are fabricated into the box. Satellite Trucks are generally referred to as 'fixed load' vehicles, meaning that the amount of equipment on-board generally does not change and the weight of the truck (other than fuel) ordinarily does not fluctuate.

Regulations[edit]

Some of the larger satellite trucks weigh over 26, 001 lbs, and therefore require the driver to obtain a Commercial Driver's License (CDL). Satellite trucks over 10, 000 lbs GVWR are required to stop at weigh stations, undergo annual DOT inspections, and the Truck driver (usually also operates the truck) needs to pass a physical examination mandated by the DOT, maintain an accurate Drivers Daily Logbook, and comply with Hours of Service rules for professional drivers.. Satellite Trucks part of a commercial fleet, or weighing over 10, 000 lbs are considered commercial vehicles by the United States Department of Transportation (DOT).

Some newer generation satellite trucks are also being used for crisis communications and command and control centers for law enforcement (homeland security) emergency managers and public utility companies.

The fact that these trucks do not rely upon terrestrial (land based signals received through a conventional aerial) communication systems makes them ideal for information distribution and bandwidth creation in the aftermath of severe tropical cyclones, floods, and earthquakes when these land based systems are damaged or destroyed. In the wake of hurricane Katrina, when the communication ability of news media outlets far exceeded that of many federal and state relief agencies, many governmental bodies have since migrated to a mobile satellite based communication platform.

C-Band satellite truck[edit]

In the United States, C-Band Transportable uplinks ("Transportable Earth Station" (TES) or Satellite Truck) was initially used to transmit longer-format live television like sports television events and entertainment television programming. C-band satellite transmission require a larger antenna than the Ku band trucks developed later in the 1980s; and a larger satellite antenna takes longer to set up and deploy.

Prior to dispatch of a C Band transportable uplink, an RF Interference study needs to be completed. An RFI is a computer-generated report detailing any FCC protected microwave stations in the immediate area. This "frequency coordination" process has to be completed before an uplink transmission can commence. Terrestrial point-to-point signals share C-Band transmit frequencies (5.700-6.500 GHz), and full-time terrestrial signals take priority over ad hoc (temporary) C-Band uplink transmissions. Factors such as terrain, buildings and other structures are considered when determining the likelihood of interference from the TES.

Historically, it was necessary to install land telephone lines (also called hard or wired lines) where the TES was located. This was expensive and difficult to do at the time, since telephone companies were not used to setting up phone lines without notice of several days or even weeks. Early scrambling or encryption methods required a hard line for authorization of receive sites. Today, a digital cellular telephone is sufficient for most situations.

C-Band transportable service remained a prevalent source of long haul transmission because of its immunity to the "rain fade" that Ku band experiences in significant rainstorms. C-Band transportable services cost more than similar Ku service due to the robust nature of the signal, the larger physical size of the truck, and specialized nature of C-Band transmissions.

With the advent of Ku band trucks (that don't require frequency coordination) and long-haul fiber optics providing similar signal qualities, C-Band transportable service experienced a slowdown in service volume in the 1990s. It's still used in situations where rain-fades (a problem affecting only Ku band uplinks) are unacceptable and where fiber-optic links are not practical. C-Band uplinks are still commonly used for golf, auto racing, horse racing, and major college sports events in rural areas where local fiber interconnects to long-haul networks are either not available or where the low number of events at the venue per year made installation of fiber not cost effective. Ku TES outnumber C perhaps 30:1, when you consider the number of TV Station, Network and "freelance" Ku trucks versus the limited number of C Band trucks.

Even with diminished usage, C-Band transportable services are still utilized as an alternate to fiber optic cross-country transport as an 'alternate' transmission path. Most broadcast networks utilize both in order to protect their remote broadcasts that may be worth millions in rightholder fees.

In the 2000 era, High Definition Television (HDTV) remote broadcasts caused a resurgence in C-Band transportable uplink service. The major factor in the resurgence was the limited amount of available bandwidth in local and long haul fiber optic service, while uplink systems merely required installation of High Definition MPEG digital encoders and decoders at either end.

See also:

• Delavnica