I Know Computers Well

The recent development of satellite radio received a lot of newspaper and web page space, as well as plenty of attention from traditional media channels. There are a few things that are changing rapidly in satellite radio, changes that may or may not affect the future of the XM and Sirius Satellite Radio companies, as well as the consumers. A few major steps towards the dynamic development of satellite radio have given consumers and financial analysts different perspectives from which to analyze this phenomenon. With the MLB moving away from terrestrial radio and heading for digital radio transmissions, with a Playboy Satellite Radio channel that has over a million subscribers and several other impressive developments, we can say that satellite radio is on an ascending path. An abrupt one, filled with shock news and unexpected developments, but ascending nevertheless. An interesting idea is the one that XM and Sirius are working on a single receiver unit that can receive broadcasts from both major satellite radio broadcasters. Another event that rocked the satellite radio world was Howard Stern’s online streaming on Sirius. His appearance on the Sirius Satellite Radio gave a new light on the Sirius company, as one that offers more than radios and broadcasting means ?as one that offers genuine content.

Terrestrial versus satellite

One of the problems XM and Sirius have had is with making the satellite receiver something desirable, cheap and effective. In the beginning the satellite receivers were large and expensive, and performed poorly on moving vehicles. Of course, the modern satellite receivers are much better, very small and compact and offer excellent reception in any area. The digital quality of the satellite radio has some amazing benefits on its own since there are no noise disturbances that were traditional to FM and AM broadcasts. Both XM Radio and Sirius Radio can be picked up on all the US territory and they are also available in some parts of Canada and Mexico. Since the direct line of sight from the satellite to the receiver may often become obstructed by landscape or buildings, land based devices were installed in order to eliminate the lack of direct satellite transmission The broad range of broadcast and the superior sound quality have taken satellite radio high in the preferences of the consumers. On the other hand, terrestrial radio has some strong points of its own. To begin with, it’s free and readily accessible to anyone. Also, terrestrial radio is so common, widespread and easy to use that anyone can enjoy it and most people don’t find it hard to actually create their radio stations. Many people are reluctant to move on to satellite radio, which is more complex and complicated.

The end consumer – the real winner

In this battle of the radios, the end consumer is the one that gets the most benefits. And since the competition got even more fierce when satellite radio started taking away subscribers of regular radio, things have gone one step further. Also, the competition between XM Radio and Sirius is in the benefit of the subscribers. An interesting aspect of the competition between the two satellite industry giants was realized by Interoperable Technologies – a joint effort funded by both Sirius and XM Radio, with the intention of bringing dual-subscription satellite radios to the general market. Analysts expect to see even more development in this direction, with XM Radio and Sirius entangled in a strange relationship, where they are working together on one project and battling it out on the satellite radio broadcasters market. In order to understand the way online streaming develops and the changes in the way satellite radios work we have to keep an eye open to the industry giants but also to the companies looking to obtain a license from the FCC. One thing is certain, however – no matter if satellite radio or terrestrial radio come up with new ways of attracting customers, the end users are the ones who will always come on top.

Any song you hear on satellite radio stars as a recording in a specific format on different recording mediums. IN most cases, the recording quality has to be maintained fairly high, usually around 384kb/s, while also being reasonably small enough to be transported on CDs and DVDs. The music tracks used in satellite radio are cataloged using a similar system to the MP3 cataloging criteria, the ID3 tags. The choice for the music tracks that will be played is made by each channel individually. The DJ selecting the tracks usually chooses about 20-30 minutes worth of music. The DJ has to listen to the tracks to make sure they are in proper condition and then simply lets the computer decode the original file. The same thing is repeated once the initial 20-30 minutes are exhausted and the music playing cycle repeats itself.

Sound encoding in satellite radio

Encoding is one of the key elements of digital radio. Each channel is handled by a different encoder. The encoder basically takes the analog file and turns it into a digital one. The digitalization process is made in real time and the music files are transformed into 1’s and 0’s. This process is carried out by powerful computers that analyze sound waves and frequency and break them into binary code. The encoding process is carried out at 128kb/s, 44.1Kh which is actually CD quality. After the song is encoded, it is transmitted to a multiplexer where other channels are also present – the multiplexer basically takes all the channels of the satellite radio provider and combines them into a single broadcast transmission. The data is then sent to a satellite modem device which modulates the data and sends it to the broadcaster’s satellites, using unique transmission frequencies.
What happens above the Earth
Here is where the satellites are located. They receive the transmission and transmit it to the receivers we have in our homes and cars. The satellites are located at 23,000 miles above us – both Sirius and XM Radio use satellites located at this distance from the Earth. The satellites are located in geo-sync, which means that hey orbit above the location they are designated to service at all times. When the satellite receives the transmission encoded at 128kb/s, 44.1 khz it rebroadcasts it to the geographical area it covers. Both Sirius and XM Radio use satellites that cover certain areas of the United states ?mostly the East and West coasts. For example, one of XM Radio’s satellites covers the western part of USA, probably an area located roughly from Seattle to San Diego on the West and Minneapolis to Houston on the east. The increased sound quality is possible because the broadcasted data (music tracks, news, sports transmission) don’t get sliced up too many times in the decoding process.

The antenna
The antenna connected to your satellite radio receiver picks up the transmission on L-Band. The recent technological advances have allowed digital radio broadcasters to create receivers small enough to fit mobile locations. In the early days of satellite radio, a large parabolic dish would have to be mounted on the car in order to receive signal. Also, before the more compact receivers were created, the early satellite radio receivers needed electronic movements that directed the dish towards the satellite line of sight. Modern flat panel receivers have eliminated all the problems of their predecessors and can be fitted almost anywhere without taking up too much space.
The receiver and the output
The receiver is the device that decodes the data, basically doing the exact opposite of what the encoding process was like. After receiving the signal from the antenna it amplifies it and converts it to usable sound. The car or home audio system is then able to play the selected satellite radio channel. The rest of the process is exactly like analog broadcasts would work, with an amplifier and speakers outputting the sound.