Wireless communications has experienced explosive growth over the last few decades, especially the cellular communications. The first-generation cellular systems emerged in the 1980s, and the systems were analogue and voice-centric. Those systems were typically limited in capacity. The second-generation cellular systems appeared about 10 years later with improved capacity, and were digital and voice centric with limited data capacities. Since the second-generation systems were not capable of supporting the high bandwidth applications, third-generation systems were developed to support multimedia services, such as audio, video, real time video conferencing or high-speed Internet connection. The standards of 3G mobile communications systems include Universal Mobile Telecommunications Systems (UMTS) WCDMA and CDMA-2000 Systems. In addition to cellular networks, other wireless networks have also emerged, such as wireless Local Area Networks (WLAN), Wireless Wide Area Network (WWAN), wireless ad hoc systems, wireless sensor networks, etc. Next-generation communications systems are expected to integrate various communications networks, support fully integrated services, and provide full coverage and ubiquitous mobile access.

Mobile radio communications refers to transferring information through electromagnetic signal over the wireless radio channel between mobile users. In contrast to the wireline channel, the wireless channel is random and time-varying. As a signal propagates over the air, the signal may get reflected, diffracted, or scattered. Therefore, the received signal at the receiver usually consists of multiple components corresponding to each distinct path. Since each multipath component has different attenuation gain and delay, the addition of multipath components may contribute constructive or destructive interference, which makes the received signal unpredictable. In addition, when the transmitter, the receiver, or the surrounding objects move, the multipath changes over time, which makes the wireless channel random and time-varying. Due to the nature of wireless channels, the design of wireless systems is fundamentally different from the one of wireline systems.

The tutorial will cover the standards and architecture of WCDMA and CDMA2000 systems, both based on spread spectrum concepts. Various protocol layers, their functions and interfaces, relationships to Intelligent Networks, and the evolution to future standards including all-IP networks will be introduced. Topics include Radio access, air interface, resource management, logical and physical channels, signaling and call processing, hand-offs and inter-working, and various voice and data scenarios. Various building blocks including User Equipment (UE), radio network, circuit and packet core networks, and associated peripherals will be discussed. The relationship to and evolution from the 2G wireless standards are also covered.