Monthly Archives: August 2012

Building the New on Top of the Old

When you use the good, old-fashioned phone, you’re getting a narrowband connection. That muffled, telephone-y quality is the result of filtering the bottom 4kHz (actually less) of the frequencies from your voice, where the majority of the energy resides. It’s …

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Posted in Digital Communication, Industry, Multimedia

Secure VoIP from the Silent Circle

One of the speakers at the recent ClueCon was Phil Zimmermann, inventor of Pretty Good Privacy (PGP). Now divested of PGP (which belongs to Symantec), Zimmermann has turned his security skills towards something called Silent Circle that allows VoIP and …

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Posted in Digital Communication, Events, security

Hooke, Dr Hook and OFDM

Isaac Newton said that he had seen further by “standing on the shoulders of giants”, and this is very applicable in the area of digital signal processing (DSP) which has a long academic history (certainly from the 1940s), but a …

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Posted in Digital Communication, Mobile