Design considerations for channelizer based receivers in generalized frequency division multiplexed OFDM systems

• Published in: Analog integrated circuits and signal processing Vol. 91; no. 2; pp. 315 - 327
• Main Authors: Harris, Fred J., Dick, Chris, Venosa, Elettra, Chen, Xiaofei
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.05.2017; Springer Nature B.V
• Subjects: Circuits and Systems; Demodulation; Electrical Engineering; Engineering; Fourier transforms; Offsets; Orthogonal Frequency Division Multiplexing; Orthogonality; Receivers; Signal,Image and Speech Processing; Spectrum allocation; User requirements; Single carrier OFDM; Channelized OFDM; Channelizer
• ISSN: 0925-1030; 1573-1979
• DOI: 10.1007/s10470-017-0938-y

An orthogonal frequency division multiplex signal delivered to receiver’s discrete Fourier transform (DFT) can be easily partitioned when the signal components have been assembled in a single modulator. This is because the signal contains the phase, frequency, and time aligned basis set components of the inverse DFT. In order to demodulate a composite signal set formed by multiple users each contributing a disjoint subset of the basis set, their transmissions must be coordinated to assure their separate contributions are time and frequency aligned at the receiver’s antenna to maintain their mutual orthogonality required for DFT based demodulation. When a large number of users access the single receiver, it becomes quite difficult to coordinate transmission time and frequency offsets of each user, to assure orthogonality in the DFT. Channelizers hold the promise of user orthogonality as a channelizer property as opposed to a DFT property. Here we consider and demonstrate one channelizer contender for cell site receivers.