The relationship between the degree of overlap in direct modulation chirp spread spectrum systems with binary phase shift keying and intersymbol interference (ISI) is analyzed. It is observed that the ISI due to overlap fluctuates or monotonically increases as the number of overlaps changes and that, in some cases, the overlap does not incur ISI at all. key words: CSS, DM, BER, chirp, overlap

A rateless transmission architecture is developed for communication over Gaussian intersymbol interference channels, based on the concept of super-Nyquist (SNQ) signaling. In such systems, the signaling rate is chosen significantly higher than the Nyquist rate of the system. We show that such signaling, when used in conjunction with good “off-the-shelf” base codes, simple linear redundancy, and...

The members of the Committee appointed to examine the dissertation of YIMING CHEN find it satisfactory and recommend that it be accepted. ii ACKNOWLEDGEMENT I would like to express my gratitude to my advisor, Dr. Benjamin Belzer and co-advisor, Dr. Krishnamoorthy Sivakumar, for their devoted guidance, continuous encouragement and support, and constructive suggestions throughout this research wo...

The impact of diversity combining on the matched filter bound of BPSK on time-discrete multipath slowly Rayleigh fading intersymbol interference channels is analysed. Expressions for the bound are derived for SNR selection, S+N selection, and also equal gain diversity combining. Numerical results for the derived bounds are presented on a GSM typical urban channel model.

An analog adaptive decision-feedback equalizer (DFE) is described. The DFE cancels intersymbol interference using four feedback taps and a fifth tap cancels DC offset. The coefficient for each tap is adapted using a small mixed-signal integrator. The DFE dissipates 220 mW at a data rate of 150 Mb/s. The active area is 1.8 mm2 in a 1mm CMOS process.

A simple technique for removing intersymbol interference (ISI) introduced by “linearly frequency-selective” fading channels is presented. The technique involves the optimization of the overall impulse response of the transmit and receive filters and effectively reduces the channel to one which is flat fading. Computer simulation results show that this equalization method works for channels with...

In this paper we propose a matched decoding scheme for convolutionally encoded transmission over intersymbol interference (ISI) channels and devise a nonlinear trellis description. As an application we show that for coded continuous phase modulation (CPM) using a non–coherent receiver the number of states of the super trellis can be significantly reduced by means of a matched non–linear trellis...

An amplitude-optimised bit-edge equalisation (BEE) scheme is presented and compared with pulse-width modulation for mitigating intersymbol interference in high-speed backplane applications. With transmitter pre-coding and pre-emphasis, this BEE uses an adaptive LMS algorithm as a receiver error convergence engine by adjusting error derivation points. The optimality of the proposed BEE scheme is...

Efficient Communication over Additive White Gaussian Noise and Intersymbol Interference Channels Using Chaotic Sequences by Brian Chen B.S.E., University of Michigan (1994) Submitted to the Department of Electrical Engineering and Computer Science in partial fulfillment of the requirements for the degree of Master of Science in Electrical Engineering at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY...

This correspondence studies robustness properties of the constant modulus (CM) criterion and the constant modulus algorithm (CMA) to the suboptimal but practical situation where the number of fractionally spaced equalizer coefficients is less than what is needed to remove all intersymbol interference (ISI). Hence, there necessarily exists an error in the equalized signal. Relationships between ...