Portal de Periódicos da CAPES

Measurement of scintillation and link margin for the TerraLink laser communication system

1998; SPIE; Linguagem: Inglês

10.1117/12.301021

1996-756X

Isaac I. Kim, Joseph Koontz, Harel Hakakha, Prasanna Adhikari, Ron Stieger, Carter Moursund, Micah Barclay, Alyssa Stanford, Richard Ruigrok, John J. Schuster, Eric J. Korevaar,

Optical Systems and Laser Technology

AstroTerra's TerraLink TM 8-155 laser communications equipment is designed for a clear weather range of 8 km and a data rate of 230 Mb/s, and TerraLink 4-155 is designed for a 2 km range. The TerraLink equipment achieves a reduction in scintillation-induced intensity fluctuations by using large receive apertures and multiple transmit apertures. We present measurements of received intensity fluctuations at different ranges through 4 inch and 8 inch receive apertures. We also present link margin data, with its implications for use of lasercom equipment in various weather conditions. Scintillation measurements were made while a communications link was operating by placing a second receive telescope with a PIN photodiode next to one of the lasercom transceivers. By plotting the probability of intensity vs. intensity, the necessary link margin to achieve a desired burst error rate can be calculated. At the longest ranges, the TerraLink equipment requires a scintillation fade margin of about 10 dB to achieve a 10 -9 bit error rate. The equipment is designed with an additional margin of 4 - 5 dB for atmospheric attenuation.