The XM system is supported with two satellites by Hughes and digital technology by Alcatel .  The XM satellites, affectionately known as "XM Rock" and "XM Roll," were launched by Sea Launch of Long Beach, California, in 2001.  They have been broadcasting Nationwide since late 2001.  

In addition to having a slightly less robust satellite constellation than Sirius, there are reports that their expected satellite lifetime is somewhat less than originally estimated.  Consequently, XM relies more on ground repeaters.  While this may not seem like a significant disadvantage, it puts XM at greater risk from the legal ramifications of IB 95-91 and UWB develolpments. In addition, XM has come under some fire from regional wireless carriers although it is believed that this dispute has now been resolved. To complicate matters, XM was awarded a patent that would allow it to compete in the local radio arena, a development that foments even more hostility from the National Association of Broadcasters .  

Both Sirius and XM are in a dispute with Fusion Lighting over their microwave-powered light bulbs. Apparently their product is capable of interfering with satellite radio transmissions, something that might give pause to potential satellite radio customers. In addition to competing with satellite radio in the legal arena, terrestrial broadcasters appear ready to pursue their own flavor of digital transmissions. Known as in-band on-channel (IBOC) terrestrial radio, the new service should be ready for prime time in 2003 thanks to a new chipset by Texas Instruments . CommVerge magazine reviews this exciting new technology that promises to offer some serious competition to satellite radio. The Toronto Star has also reviewed this new development.

The IEEE has conducted a complete review of satellite radio technology.

Silicon Labs of Austin, Texas has developed a CMOS synthesizer for satellite radios manufactured for XM.  The new RF component allows the development of a chip set that reduces the component count needed to build a radio by 70 percent.  Together with digital baseband chips from Agere , ST Microelectronics , mixers and IF components from Analog Devices , and downconverters from Maxim , it permits the fabrication of more compact XM receivers.  (28 October 2003)


XM is assembling its next generation chipset with the inclusion with a new intermediate frequency (IF) surface acoustic wave (SAW) filter from RF Monolithics .  The chipmaker's director of communications products, Dr. Jidong Dai said "We are extremely pleased to be one of the providers of IF filters for XM's receivers.  RFM filters contribute significantly to two of the major technical improvements that make the new-generation XM radio happen."  (6 November 2003)