This presentation describes the classical theoretical limitations for antenna size based on seminal work by several researchers. Antenna volume or “size” can be related to antenna “Q” (Quality Factor) based on the so-called Chu-Harrington Limit. The “Q” is generally accepted to be a measure of antenna bandwidth, although describing a precise relationship for UWB is difficult. Nevertheless, an understanding of the general trend described by such theoretical considerations can contribute to the successful design of portable ultra-wideband devices
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发表于 2006-10-11 19:02:00
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