Digital Transmission Evaluation Project DR8A Test.
Abstract
The Avantek DR8A radio was tested in back-to-back configuration and an actual link configuration to determine transfer parameters and to refine standard test techniques. The radio operates at a baseband rate of 12.5526 Mb/s (192 voice channels) in a 7 MHz bandwidth in the 8GHz band. The modulation technique is quadrature phase partial response (QPR). BER vs RSL characteristics are displayed as the primary mode of equipment evaluation. Carrier-to-interference data and diversity switching error data are presented. The power spectrum is displayed showing 99% power bandwidth points and masks for the FCC emission limitations. The mean BER vs RSL curve is displayed approximately 4 dB from the theoretical, with about a 3.5 dB maximum variation among transmitter-receiver combinations. The 99% power bandwidth is 6 MHz, and application of the mask indicates compliance with the FCC digital limitations, after assumptions. C/I results show that the 18 dB ratio is the lowest tolerable, with a mean BER plateau of 0.0001, at higher RSL's. Receiver diversity switching results confirm errorless operation. Link bit error rate unavailability is quantified graphically. Increased amplification of transmitted signal was possible to 5.0 watts without serious degradation. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 30, 1977
- Accession Number
- ADA040234
Entities
People
- Henry S. Walczyklink
- James E. Hamant
- O. P. Connell