| Ever wonder how this whole satellite radio | | | | the ground station and bounces it back to us. |
| thing works? I mean, it seems to be THE | | | | Because the signal is digital, it can be |
| thing now. Many auto manufacturers are | | | | compressed and beamed out packed full of |
| installing satellite radio receivers in their | | | | additional data (disguised as 0's and 1's), |
| new automobiles, and there are home and | | | | and received by any satellite radio receiver |
| portable models available through your | | | | tuned to the signal. Satellite radio |
| favorite electronics outlet. But what is it? | | | | receivers can pick up the broadcast from |
| How does it work? Why should I pay for | | | | anywhere in the coverage area (meaning the |
| radio? | | | | whole US) because the satellite is orbiting |
| | | | at about 22,200 miles (35,000 km) above the |
| You pay for TV, don't you? | | | | earth, which allows for a greater dispersion |
| | | | of the signal. It's analogous to water |
| Once, in those long gone days of yore, cable | | | | flowing from a showerhead. An inch from the |
| television operators offered us television, | | | | showerhead, the water is a relatively tight |
| which we had happily been receiving for free | | | | stream. At the other end of the shower, the |
| through big tree-branchy things on our roofs, | | | | water sprays all over the wall, and gets on |
| for a fee. Many people scoffed at the idea | | | | the bathroom floor, causing your wife to yell |
| of paying for 30 channels when they received | | | | angrily about the mess. Satellite radio |
| four or five, gratis. Well, just look at us | | | | beams work in much the same way. The radio |
| now - cable TV, satellite TV, 500 channels | | | | signal is much more widely dispersed 22,000 |
| not quite filling us up. So let's stop | | | | miles from the satellite that sent the |
| asking questions about why you should pay for | | | | signal. So with satellite radio, you can |
| satellite radio, and let's find out how the | | | | listen to the same station as you drive from |
| dern thing works. | | | | New York City to Los Angeles, whereas |
| | | | traditional radio has a range of only about |
| Well, how does the dern thing work? | | | | 30 to 40 miles. And thanks to repeaters, or |
| | | | signal boosters, placed in urban areas, you |
| Let's start by looking at the type of radio | | | | can receive generally uninterrupted signals |
| you are used to. AM radio broadcasts at a | | | | even driving through cities with large |
| frequency range from 535 kilohertz (kHz) to | | | | buildings and thick bridges. |
| 1700 kilohertz (1.7 MHz). FM broadcasts | | | | |
| between 88 MHz to 108 MHz. Without getting | | | | Hey, that's kind of cool! |
| too technical, one hertz is basically one | | | | |
| cycle per second. So FM radio waves | | | | But wait! There's much, much more! The |
| transmitted at 88MHz are cycling 88 million | | | | digital signal can carry much larger packets |
| times per second. This seems like a lot, but | | | | of data, and satellite radios are equipped |
| is actually relatively slow. Slower cycles | | | | with chipsets, or processors, that can decode |
| require larger antennas to transmit and to | | | | that data. So satellite radios not only play |
| receive them. Also, radio station antennas | | | | the music, but also decode and display |
| are stationary and earthbound, and are | | | | information containing the song title, album, |
| therefore limited in range. At higher | | | | artist, and genre. Satellite radio owners |
| cycles, smaller antennas suffice. Cell | | | | can also choose from hundreds of stations, |
| phones range from 824 MHz to 1990 MHz | | | | which allows for specialization, just like |
| (1.99GHz), depending on the type of service; | | | | your cable or satellite TV. In the same |
| this is a much faster cycle, and therefore a | | | | manner that you can get the HBO Comedy Hits |
| smaller antenna is used. Satellite radio is | | | | of the Brahman Caste of Nepal Channel, and |
| broadcast at 2.3 GHz, so your car or portable | | | | Tasmanian Worm Wrestling on ESPN 127, you can |
| receiver has no trouble picking up the | | | | receive niche music, comedy, news, and sports |
| signal. There have also been great advances | | | | broadcasts on your satellite radio. Pick |
| in antenna technology, which provide us with | | | | your genre: any decade since the 40's, Rock, |
| a relatively small, flat antenna rather than | | | | Country, Urban, Jazz, Blues, Dance, Latin, |
| a dish that would have to be constantly | | | | World Music (e.g. Chinese, Indian, African), |
| adjusted to point toward the satellite as we | | | | Classical, Kids, and even news, sports, |
| drove around town picking up kids from soccer | | | | comedy, and talk. You can also tune in to |
| practice. | | | | any sub-genre of the above; for example, in |
| | | | the Rock category you can listen to soft, |
| All them numbers hertz my brain. | | | | heavy, classic, deep cuts, acoustic, |
| | | | instrumental, and even unsigned acts. |
| Let's lay megahertz and gigahertz aside for a | | | | |
| moment. In addition to those higher | | | | Maybe I should get me one of them there |
| frequencies, satellite radio signals come | | | | satellite radios... |
| from, you guessed it, satellites. These | | | | |
| satellites are in a geosynchronous orbit, | | | | Now that you know how it works, you can |
| which is an orbit that keeps the satellite | | | | listen for the sheer pleasure of it - without |
| always above one location on the planet, | | | | all those nagging technical questions |
| making it stationary relative to the earth. | | | | churning in the back of your mind. Go get |
| The satellite receives a digital signal from | | | | you one. |