Industry-Standard Satellite Link Emulator Gets A Makeover

Service calls to geosynchronous orbit being rather expensive, fully characterizing the performance of a satellite communications system before launch is obviously essential. To do this, characteristics such as propagation delay, fading, Doppler shift, and phase shift must be produced by test systems at precise levels and times to accurately mimic the conditions that occur as a satellite changes its position in the sky. dBm has long offered a satellite link emulator (appropriately called the SLE), which provides the transmission path and signal impairments. It has been used for many satellite programs over the years for testing Earth terminals as well as payloads. Now the company has made dramatic improvements to the design of the SLE in its latest incarnation, the SLE700.

The instrument's performance in nearly every key RF parameter has been improved, including greater delay accuracy, a 15-dB improvement in spurious rejection, and lower noise floor. Maximum RF bandwidth is now 45 MHz versus 20 MHz in order to accommodate the wider modulation schemes employed in current satellite communications systems. Signal-to-noise ratio has been improved by 15 dB as well.

© Appeared in the May 2006 edition of Microwave Product Digest