Title :
Improving ACIPR for land mobile radio systems using coded modulation
Author :
Chennakeshu, Sandeep ; Ramesh, R. ; Hassan, Amer A. ; Anderson, John B.
Author_Institution :
General Electric Co., Schenectady, NY, USA
Abstract :
The spectral efficiency for land mobile radio (LMR) systems is primarily limited by adjacent channel interference (ACI). Conventional digital modulation schemes do not meet current ACI protection specifications, unless augmented by powerful interference mitigation techniques. High spectral efficiency and ACI protection can be achieved by using trellis codes that are specifically designed to maximize the adjacent channel interference protection ratio (ACIPR). A spectral optimization is done in conjunction with appropriate transmit and receive filters and constraints on peak-to-average transmit power ratio and minimum distance of the code. The theory of spectral shaping to maximize ACIPR is discussed, and examples are presented to illustrate the potential of the approach for LMR systems
Keywords :
mobile radio systems; radiofrequency interference; spectral analysis; trellis codes; ACI; ACIPR; adjacent channel interference; adjacent channel interference protection ratio; coded modulation; land mobile radio systems; minimum code distance; peak-to-average transmit power ratio; spectral efficiency; spectral optimization; spectral shaping; trellis codes; Bandwidth; Bit error rate; Euclidean distance; Filters; Frequency response; Interference; Land mobile radio; Modulation coding; Radio transmitters; Shift registers;
Conference_Titel :
Vehicular Technology Conference, 1992, IEEE 42nd
Conference_Location :
Denver, CO
Print_ISBN :
0-7803-0673-2
DOI :
10.1109/VETEC.1992.245291
