Symbol Technologies Spectrum24 AP-4131 - Manual (Page 28)

Introduction
18 AP-4131 Access Point Product Reference Guide
1.3.5 Direct-Sequence Spread Spectrum
Spread spectrum (broadband) uses a narrowband signal to spread the
transmission over a segment of the radio frequency band or spectrum.
Direct-sequence is a spread spectrum technique where the transmitted signal
is spread over a particular frequency range. The Spectrum24 AP-4131access
point uses Direct-Sequence Spread Spectrum (DSSS) for radio
communication.
Direct-sequence systems communicate by continuously transmitting a
redundant pattern of bits called a chipping sequence. Each bit of transmitted
data is mapped into chips by the access point and rearranged into a
pseudorandom spreading code to form the chipping sequence. The chipping
sequence is combined with a transmitted data stream to produce the AP
output signal.