Modulation and Power Spectrum

Modulation is the process whereby message information is embedded into a radio frequency carrier. Such information can be transmitted in either the amplitude, frequency, or phase of the carrier, or a combination thereof. This chapter begins with the basis mathematical representation of digitally modulated signals. This is followed by a discussion of Nyquist pulse shaping, which is essentially for spectral control. Afterwards, the chapter considers a large number of digital modulation schemes that are commonly employed in wireless communication systems, including quadrature amplitude modulation, phase shift keying techniques, orthogonal modulation and variants, orthogonal frequency division multiplexing, and continuous phase modulation. The chapter concludes with a thorough treatment of the power spectrum of the various digitally modulated waveforms considered in the chapter.

[1]  I. Sandberg.  Floating-point-roundoff accumulation in digital-filter realizations , 1967 .

[2]  M. A. Birchler,et al.  A 64 kbps digital land mobile radio system employing M-16QAM , 1992, 1992 IEEE International Conference on Selected Topics in Wireless Communications.

[3]  Subbarayan Pasupathy.  Nyquist's third criterion , 1974 .

[4]  F. Jager,et al.  Tamed Frequency Modulation, A Novel Method to Achieve Spectrum Economy in Digital Transmission , 1978, IEEE Trans. Commun..

[5]  S. Weinstein,et al.  Data Transmission by Frequency-Division Multiplexing Using the Discrete Fourier Transform , 1971 .

[6]  Pierre A. Laurent,et al.  Exact and Approximate Construction of Digital Phase Modulations by Superposition of Amplitude Modulated Pulses (AMP) , 1986, IEEE Trans. Commun..

[7]  Leonard J. Cimini,et al.  Analysis and Simulation of a Digital Mobile Channel Using Orthogonal Frequency Division Multiplexing , 1985, IEEE Trans. Commun..

[8]  C. E. SHANNON,et al.  A mathematical theory of communication , 1948, MOCO.

[9]  R. Chang.  Synthesis of band-limited orthogonal signals for multichannel data transmission , 1966 .

[10]  G. Garrison,et al.  A Power Spectral Density Analysis for Digital FM , 1975, IEEE Trans. Commun..

[11]  Claude E. Shannon,et al.  A mathematical theory of communication , 1948, MOCO.

[12]  Harry Nyquist.  Certain Topics in Telegraph Transmission Theory , 1928 .

[13]  K. Hirade,et al.  GMSK Modulation for Digital Mobile Radio Telephony , 1981, IEEE Trans. Commun..