Murata Electronics North America DNT24 Manual De Usuario
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DNT24 Integration Guide – 03/04/15
Narrow-band versus spread spectrum transmission
Figure 1.1.1
1.2 Frequency Hopping versus Direct Sequence
The two primary approaches to spread spectrum are direct sequence spread spectrum (DSSS) and fre-
quency hopping spread spectrum (FHSS), either of which can generally be adapted to a given applica-
tion. Direct sequence spread spectrum is produced by multiplying the transmitted data stream by a much
faster, noise-like repeating pattern. The ratio by which this modulating pattern exceeds the bit rate of the
base-band data is called the processing gain, and is equal to the amount of rejection the system affords
against narrow-band interference from multipath and jammers. Transmitting the data signal as usual, but
varying the carrier frequency rapidly according to a pseudo-random pattern over a broad range of chan-
nels produces a frequency hopping spectrum system.
quency hopping spread spectrum (FHSS), either of which can generally be adapted to a given applica-
tion. Direct sequence spread spectrum is produced by multiplying the transmitted data stream by a much
faster, noise-like repeating pattern. The ratio by which this modulating pattern exceeds the bit rate of the
base-band data is called the processing gain, and is equal to the amount of rejection the system affords
against narrow-band interference from multipath and jammers. Transmitting the data signal as usual, but
varying the carrier frequency rapidly according to a pseudo-random pattern over a broad range of chan-
nels produces a frequency hopping spectrum system.
Forms of spread spectrum - direct sequence and frequency hopping
Figure 1.1.2