HFA3863 データシートの表示（PDF） - Intersil

部品番号

コンポーネント説明

一致するリスト

HFA3863

Direct Sequence Spread Spectrum Baseband Processor

Intersil 

HFA3863

consecutive SQ1’s will cause the part to finish the

acquisition phase and enter the tracking phase.

Prior to initial acquisition the NCO is inactive (0Hz) and

carrier phase measurement are done on a symbol by symbol

basis. After acquisition, coherent DPSK demodulation is in

effect. After a brief setup time as illustrated on the timeline,

the signal begins to emerge from the demodulator.

It takes 7 more symbols to seed the descrambler before

valid data is available. This occurs in time for the SFD to be

received. At this time the demodulator is tracking and in the

coherent PSK demodulation mode so it will no longer

acquire new signals. If a much larger signal overrides the

signal being demodulated (a collision), the demodulator will

abort the tracking process and attempt to acquire the new

signal. Failure to find an SFD within the SFD timeout

interval will result in a receiver reset and return to

acquisition mode.

TX

POWER

RAMP

2

20 SYMBOLS

AGC SETTLE AND LOCK

AND INITIAL DETECTION

56 SYMBOL SYNC

20 SYMBOLS

7 SYM

VERIFY AND CIR/FREQUENCY

ESTIMATION AND CMF/NCO

JAMMING

SEED

DESCRAMBLER

START SFD SEARCH

FIGURE 10. ACQUISITION TIMELINE, NON DIVERSITY

SFD

16 SYMBOLS

SFD DET

START DATA

4-15

Share Link: