Features
The WAN Access Challenge for Small and Branch Offices
By Nabil G. Damouny
WAN access has evolved from an early environment consisting entirely of privately leased lines, to an environment that includes several dial-up
approaches (analog and digital) and both narrowband and broadband connections. This article examines, on an architectural level, the problems and available solutions in small-office and branch-office WAN access.
Analog in a Digital Dementia
By John Wright
Attempting to mix analog and digital functions on the same chip can be a recipe for frustration — if not dementia! Here’s an approach that can put some sanity back into the
development process. This article highlights the critical design-flow elements that lead to a successful mixed-signal design.
The Effects of Phase Noise on High-Order QAM Systems
By Douglas Barker
In communication systems that employ high-order quadrature amplitude modulation (QAM), phase noise can be a major contributor to system performance degradation. This is particularly the case when large, dense QAM constellations are employed at
high carrier frequencies.
Echo Cancellation for VoIP
By John C. Gammel
Echo has plagued telephone systems since the dawn of telephony, but for high-speed digital transmission, the deleterious effects of echo become more severe. This article surveys echo sources in telephone networks, and various techniques for dealing with this persistent problem.
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CSD 2019
Wireless LANs Speed Up.
Puzzled by a network processing design issue?