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P. 87
Modulation
86 Chapter Two
Figure 2.40 The RF2703 IC in modulator configuration with support components.
13 is the high-impedance LO input, with 51 ohms shunted to ground for a 50-
ohm oscillator. Pin 14 is V , which must be adequately bypassed.
CC
2.6 Digital Test and Measurement
2.6.1 Introduction
This section describes new tests created to confirm proper radio operation with
digital modulations by measuring BER and generating constellation and eye
diagrams, as well as the more rigorous testing methods necessary to detect the
smaller levels of error-producing phase noise, frequency instabilities, group
delay variations, etc., found in today’s high-end digital radios. And since digi-
tal power measurement is not the same as for the narrowband analog modu-
lations, techniques for its accurate measurement will be presented, as will a
few of the more important testing procedures for QAM and QPSK wireless
devices.
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