Introduction

With the increasing demand for mobile and hence, wireless technologies, the need for more secure and reliable methods of transmitting data has grown.

The most common technique to achieve both is called spread spectrum. It is a special modulation technique that spreads the transmitted signal over a frequency range much wider than the minimum bandwidth that is required to send a signal. Widening the signal bandwidth in this fashion increases the probability that received information will closely match the transmitted information. Although spread spectrum is relatively new to commercial industry, this technique has been used by the military ever since World War II.

The vast majority of wireless communication of information is tranmitted over radio frequencies but it is not inherenantly secure.