FE Analysis of Communications Systems for Drive-Thru Restaurants in a Business Dispute Over Specifications and Design Process

Robert Peruzzi

doi:10.51501/jotnafe.v38i1.106

Authors

Robert Peruzzi, PhD, PE R. Peruzzi Consulting, Inc.

DOI:

https://doi.org/10.51501/jotnafe.v38i1.106

Keywords:

forensic engineering, fast food, quick service restaurant, QSR, drive-thru, communications system, simplex, half duplex, full duplex, two-way radio, intercom, adaptive systems, automatic gain control, AGC, noise cancelation, linear time invariant, LTI, nonlinear time-varying

Abstract

Forensic analysis in this case involves the design of a communication system intended for use in Quick Service Restaurant (QSR) drive-thru lanes. This paper provides an overview of QSR communication system components and operation and introduces communication systems and channels. This paper provides an overview of non-linear, time-varying system design as contrasted with linear, time-invariant systems and discusses best design practices. It also provides the details of how audio quality was defined and compared for two potentially competing systems. Conclusions include that one of the systems was clearly inferior to the other — mainly due to not following design techniques that were available at the time of the project.

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