In this chapter, we present the principle of spread-spectrum transmission and demonstrate the basic underlying mechanisms for its desirable features. We first discuss the most popular spectrum spreading method, direct sequence spread spectrum (DSSS). Noting that the desirable features of spread spectrum system rely heavily on the spreading signal design, we then discuss the design of spreading codes. RAKE receiver and multiple user transmission based on DSSS are considered afterwards. We conclude the chapter with a brief discussion on frequency-hopping spread spectrum (FHSS).

Chapter Contents:

• 7.1 Direct-sequence spread spectrum
• 7.1.1 Spreading code design
• 7.1.2 Effect of DSSS receiver on interference and noise
• 7.1.3 RAKE receivers
• 7.2 Multiple access with CDMA
• 7.2.1 Spreading codes for multiple access
• 7.2.2 Performance analysis
• 7.3 Frequency-hopping spread spectrum
• 7.4 Further readings
• Problems
• Bibliography

Inspec keywords: spread spectrum communication; radio receivers; code division multiple access; frequency hop communication

Other keywords: DSSS; frequency-hopping spread spectrum; direct sequence spread spectrum; FHSS; multiple-user transmission; signal design; RAKE receiver; spreading codes; spectrum spreading method; spread-spectrum transmission

Subjects: Multiple access communication; Radio links and equipment