文档介绍：An Ultra Low Cost,
Low Phase Noise VCO
A easy-to-manufacture capacitively-loaded microstrip resonating element
is the key to this economical design
By Allen Bettner
Wireless Link Corp.
he ability to achieve good phase
noise performance is paramount
Tin most wireless design.
Performance specifications that require
adjacent channel rejection as well as
transmitter signal purity are dependent
on the phase noise of the receiver local
oscillator and/or transmit local oscillator.
Oscillators capable of achieving
these goals are ing more avail-
able, but cost is still a factor when inte-
grating off-the-shelf VCOs into any
design. This article describes a method
of achieving low phase noise at
extremely low cost. The heart of the
design is a resonating structure that L Figure 1. The resonating structure used in the oscillator
can be employed directly on low cost keeps cost down while achieving low phase noise perfor-
printed circuit material and easily mance essential to wireless design.
tuned to the desired frequency in a high
volume production environment.
Both linear and nonlinear analysis of this of the resonator to achieve the proper center
oscillator has been plished using frequency. This process (grinding or laser trim-
Xpedion’s new simulator, Golden Gate. Using ming) can affect the resonator Q, lowering both
Golden