Direct sequence is a method of spread spectrum radio communications which spreads data over several bands of radio frequency. This can accomplish one of two things: firstly, this can be used in the same manner as RAID striping mode; that is, each channel may be used to send different data, and the receiver may be forced to put it all together at the end. Secondly, it may be used in the same manner as RAID mirroring; that is to say that each channel may have the same data transmitted, and the receiver must decide, from all the symbols received, what the transmitter was trying to send.

Both of these methods require multiple tuners and transmitters, making them expensive. Neither is more secure than standard singleband radio communications. Redundant method can be more interference-resistant than frequency-hopping, but still is nowhere near as secure. Striped method can be as many times faster than frequency-hopping or redundant method as there are tranceivers. This makes excellent use of limited RF bandwidth, but is extremely vulnerable to interference.
see also: frequency-hopping.
Direct sequence spread spectrum is a technique for sending a radio signal from a transmitter to a receiver.

It uses one or more channels. Each channel contains a section of the original signal, which is sent along a frequency channel to improve reliability of reception.

Additionally, on each frequency, a 'chipping code' is used. This is a essentially a non sinusoidal carrier signal. Because the chipping codes are orthogonal this can actually can allow more than one user to transmit at the same time on the same frequencies with only a minor increase in noise to each user, up to the limit described by Shannon's law.

The end result is that spread spectrum radio can be difficult to intercept and jam, and further it is relatively immune to multipath distortion.

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