Title :
Switching considerations to combat spectral pollution in TDMA for satellite broadcasting
Author :
Qi, Yusheng ; Wu, Gene ; Yang, Jiashi ; Feher, Kamilo
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., Davis, CA, USA
fDate :
6/1/1993 12:00:00 AM
Abstract :
A better switching technique for combating spectral pollution i.e. spectral spreading of burst time-division multiple access (TDMA) digital FM and π/4-QPSK (quadrature phase-shift keying) systems, is proposed. The effects of rectangular, linear, and raised cosine ramp on/off switching are examined for two prototypes using both hardware experimental methods and computer simulation for different gating rates, duty cycles, roll-off factors of transmitter filter and ramp on/off times. The measures results agree with the computer simulation results and indicate that the adjacent channel interference (ACI) caused by the burst operating in TDMA π/4-QPSK is significantly reduced by raised cosine switching in comparison with other types of switching
Keywords :
digital radio systems; direct broadcasting by satellite; mobile radio systems; phase shift keying; radio broadcasting; radiofrequency interference; time division multiple access; π/4-QPSK; ACI; TDMA; adjacent channel interference; burst time-division multiple access; computer simulation; digital FM Systems; direct broadcasting by satellite; duty cycles; gating rates; hardware; linear cosine ramp on/off switching; mobile radio; quadrature phase-shift keying; radio DBS; raised cosine ramp on/off switching; ramp on/off times; rectangular cosine ramp on/off witching; roll-off factors; satellite broadcasting; spectral pollution; spectral spreading; switching technique; transmitter filter; Communication switching; Computer simulation; Digital communication; Frequency modulation; Hardware; Pollution; Radio frequency; Satellite broadcasting; Time division multiple access; Virtual prototyping;
Journal_Title :
Broadcasting, IEEE Transactions on
