Z87200 Просмотр технического описания (PDF) - Zilog

Номер в каталоге

Компоненты Описание

Список матч

Z87200

SPREAD-SPECTRUM TRANSCEIVER

Zilog 

Zilog

Z87200

Spread-Spectrum Transceiver

Reducing the carrier frequency to 25% of the clock fre- tion in the modulator, resulting in performance degrada-

quency can reduce the distortion level, as shown in Figure tion. As a rule-of-thumb, one may restrict the I.F. frequency

4 21. Although the distortion is still fairly severe, adequate to 25% of the clock frequency, but, in general, each appli-

performance may be obtainable as a result of the system’s cation and combination of PN chip rate, I.F. frequency, and

processing gain, but the performance would be many dB TXIFCLK/RXIFCLK frequency is unique and should be

off the theoretical limit. As the PN chip rate of the system evaluated before deciding whether to use the Z87200’s in-

increases, then so, too, does the effect of aliasing distor- ternal BPSK/QPSK modulator.

Figure 19. Spectrum of DDS Modulated at 0.4 x fRXIFCLK

When Carrier Frequency is set to 0.25 x fRXIFCLK

DS96WRL0400

4-53

Share Link: