Download
1 / 37
370 likes | 501 Views
Drs. Ahmed Kurnia Soeriawidjaja M.Si. What is Satellite Radio?. Basically, it is an additional band for your radio.
E N D
What is Satellite Radio? • Basically, it is an additional band for your radio. • Unlike standard radio, which is transmitted from earth-bound transmitters, satellite radio comes primarily from a signal sent via satellites orbiting the earth directly to 3-band AM/FM/SAT radios.
The good news of Satellite Radio • Satellite radio may very well be the wave of the future because of the clarity, lack of commercials and broad range without signal interruption. • Now, imagine a radio station that can broadcast its signal from more than 35,000 km away and then come through on your car radio with complete clarity. • You could drive from Jakarta to Surabaya, without ever having to change the radio station! Not only would you never hear static interfering with your favorite tunes, but the music would be interrupted by few or no commercials.
Three space-based • At this time, there are three space-based radio broadcasters: • Sirius Satellite Radio • XM Satellite Radio • WorldSpace
Sirius and XM 1. Sirius and XM both produce live and taped programming, ranging broadly from Alanis Morissette (right), to sports and news.
2. The programming is beamed to satellites from dishes operated by satellite radio operator.
3. The satellites broadcast the signal back to Earth, where it's picked up directly by receiver units. The signal is also received and rebroadcast by repeater stations in metropolitan areas. XM uses two geostationary satellites that remain constantly above the United States. Sirius uses three satellites, two of which are always over the country.
4. A receiver buffers the broadcast for a few seconds, so if it loses the satellite signal it can use one from a repeater station, helping insure a continuous broadcast. Overpasses and tall building are particular problems.
There are 4 main differences between satellite radio and the stations provided on traditional radio: • Digital Clear Sound: Satellite radio signals are digital, and the satellites cover the entire continental US and many other countries such as Mexico. This means channels have no geographic boundaries; you can drive across the country and not have dead spots or be constantly searching for a channel you like. • Programming and Content: Sirrius and XM Radio both offer over 100 channels each. So satellite radio offers far more variety than standard radio. If you live somewhere that doesn't have many radio stations, you may find yourself pleasantly surprised but the choices and with the variety of programming now available to you. • No Commercials: All the channels on both XM Radio and Sirius are 100% commercial-free! • Cost of Satellite Radio: While broadcast radio is free, satellite radio is a subscription service. XM Radio costs $9.99/month, while Sirius is $12.95/month.
Since its debut, satellite radio has truly taken off. • By the summer of 2004, the two leading satellite radio services, XM and Sirius, have stated that they have signed up more than 3,000,000 subscribers. • With its crystal-clear digital signals, satellite radio is the new way to listen to radio, offering dozens of commercial-free, premium channels, . • Currently, most enjoy satellite radio in their cars. • With more then 100 channels of music, news, sports, and entertainment, you'll be sure to find something you want. • It's a great way to enjoy a long drive too, knowing you'll never lose a channel to static interference or poor reception.
Sirius and XM have developed slightly different technologies which means that you can purchase a radio capable of receiving satellite broadcasts from one company or the other, but not both.Both Sirius and XM have announced an agreement to develop a unified standard for satellite radios. • This "second generation" satellite radio will allow a single radio to receive broadcasts from either company. • Availability of radios conforming to this new standard has not be made available.
Satellite Radio – Car Manufacturer • Sirius Radio has partnered with Ford-Lincoln-Mercury automobiles and is available as an installed option in some models. • XM Radio has partnered with General Motors -Cadillac -Buick automobiles and is available as an installed option in some models.
Historical Background • Satellite radio is an idea over a decade in the making. • In 1992, the U.S. Federal Communications Commission (FCC) allocated a spectrum in the "S" band (2.3 GHz) for nationwide broadcasting of satellite-based Digital Audio Radio Service (DARS). • Only four companies applied for a license to broadcast over that band. • The FCC gave licenses to two of these companies in 1997. • CD Radio (now Sirius Satellite Radio) and American Mobile Radio (now XM Satellite Radio) paid more than $80 million each to use space in the S-band for digital satellite transmission.
Satellite radio companies are comparing the significance of their service to the impact that cable TV had on television 30 years ago. • Listeners won't be able to pick up local stations using satellite radio services, but they will have access to hundreds of stations offering a variety of music genres. • Each company has a different plan for its broadcasting system, but the systems do share similarities.
Taking a closer look, you will see slight variances in the three satellite radio companies' systems XM – Sirius - SpaceWorld
Hardware Here are the key components of the three satellite radio systems: • Satellites • Ground repeaters • Radio receivers
XM Radio • XM Radio uses two Boeing HS 702 satellites, appropriately dubbed "Rock" and "Roll," placed in parallel geostationary orbit, one at 85 degrees west longitude and the other at 115 degrees west longitude. • Geostationary Earth orbit (GEO) is about 22,223 miles (35,764 km) above Earth, and is the type of orbit most commonly used for communications satellites. • The first XM satellite, "Rock," was launched on March 18, 2001, with "Roll" following on May 8. XM Radio has a third HS-702 satellite on the ground ready to be launched in case one of the two orbiting satellites fails.
XM Satellite Radio • XM Radio's ground station transmits a signal to its two GEO satellites, which bounce the signals back down to radio receivers on the ground. • The radio receivers are programmed to receive and unscramble the digital data signal, which contains up to 100 channels of digital audio. • In addition to the encoded sound, the signal contains additional information about the broadcast. • The song title, artist and genre of music are all displayed on the radio. • In urban areas, where buildings can block out the satellite signal, XM's broadcasting system is supplemented by ground transmitters.
XM Radio • Each receiver contains a proprietary chipset. • XM began delivering chipsets to its XM radio manufacturing partners in October 2000. • The chipset consists of two custom integrated circuits designed by STMicroelectronics. • XM has partnered with Pioneer, Alpine, Clarion, Delphi Delco, Sony and Motorola to manufacture XM car radios. • Each satellite radio receiver uses a small, car-phone-sized antenna to receive the XM signal.
XM Radio • General Motors has invested about $100 million in XM, and Honda has also signed an agreement to use XM radios in its cars. • GM began installing XM satellite radio receivers in selected models in early 2001. • For $9.99 per month, subscribers can receive the XM signal. For that price, listeners get up to 100 channels of music, talk and news. • Many of the channels have no commercials, with none of the channels having more than seven minutes of ads per hour. XM's content providers include USA Today, BBC, CNN/Sports Illustrated and The Weather Channel. The service bolsters that lineup with its own music channels
Sirius Satellite Radio • The Sirius system is similar to that of XM. • Programs are beamed to one of the three Sirius satellites, which then transmits the signal to the ground, where your radio receiver picks up one of the channels within the signal. • Signals are also be beamed to ground repeaters for listeners in urban areas where the satellite signal can be interrupted.
Sirius Satellite Radio • Unlike XM, Sirius does not use GEO satellites. Instead, its three SS/L-1300 satellites form an inclined elliptical satellite constellation. • Sirius says the elliptical path of its satellite constellation ensures that each satellite spends about 16 hours a day over the continental United States, with at least one satellite over the country at all times. • Sirius completed its three-satellite constellation on November 30, 2000. • A fourth satellite will remain on the ground, ready to be launched if any of the three active satellites encounter transmission problems.
Sirius Satellite Radio • Sirius offers car radios and home entertainment systems, as well as car and home kits for portable use. • The Sirius receiver includes two parts -- the antenna module and the receiver module. • The antenna module picks up signals from the ground repeaters or the satellite, amplifies the signal and filters out any interference. • The signal is then passed on to the receiver module. • Inside the receiver module is a chipset consisting of eight chips. • The chipset converts the signals from 2.3 gigahertz (GHz) to a lower intermediate frequency. • Sirius also offers an adapter that allows conventional car radios to receive satellite signals.
WorldSpace • So far, WorldSpace has been the leader in the satellite radio industry. It put two of its three satellites, AfriStar and AsiaStar, in geostationary orbit before either of the other two companies launched one. • Each satellite transmits three signal beams, carrying more than 40 channels of programming, to three overlapping coverage areas of about 5.4 million square miles (14 million square km) each. • Each of the WorldSpace satellites' three beams can deliver over 40 channels of crystal clear audio and multimedia programming via the 1,467- to 1,492-megahertz (MHz) segment of the L-Band spectrum, which is allocated for digital audio broadcasting.
WorldSpace • The United States is not currently part of WorldSpace's coverage area. • WorldSpace has invested in XM Radio and has an agreement with XM to share any technological developments. • WorldSpace is going beyond one nation and eyeing world domination of the radio market. • That might be overstating the company's intent a bit, but WorldSpace does plan to reach the corners of our world that most radio stations cannot. • There are millions of people living in WorldSpace's projected listening area who cannot pick up a signal from a conventional radio station. WorldSpace says it has a potential audience of about 4.6 billion listeners spanning five continents.
WorldSpace • WorldSpace broadcasters uplink their signal to one of the three satellites through a centralized hub site or an individual feeder link station located within the global uplink beam. • The satellite then transmits the signal in one, two or all three beams on each satellite. • Receivers on the ground then pick up the signal and provide CD-quality sound through a detachable antenna. • WorldSpace satellite receivers are capable of receiving data at a rate of 128 kilobits per second (Kbps). • The receivers use the proprietary StarMan chipset, manufactured by STMicroelectronics, to receive digital signals from the satellites.
