The application of signal processing techniques to wireless communications is an emerging area that has recently achieved dramatic improvement in results and The First Generation (1G) and Second Generation (2G) of mobile telephony were indented for voice transmission. The Third Generation (3G) is meant for both voice and data applications. The thirst for effective communication and higher bandwidth has led to the evolution of the next generation wireless systems, and newer technologies are being deployed to provide the user with information and entertainment anywhere and anytime. The 3G mobile radio systems (International Mobile Telecommunication (IMT)-2000 globally and Universal Mobile Telecommunication System (UMTS) in Europe) are becoming a reality today. The network infrastructure is currently being deployed in many countries. Manufacturers, network operators and service providers are now focusing on the development of new services and applications as well as suitable business models to make 3G mobile communication an economic success. One important lesson to be learnt from the development of 3G is that the potential future services and applications, including the expected user behavior should be taken into account from the very beginning to derive the technical requirements. This approach is essential to enable the economic success of future system. The present paper deals with overview of pulse shaping in modern wireless communication in the Wideband Code Division Multiple Access (WCDMA) domain.

The rapidly increasing popularity of mobile radio services has created a series of technological challenges. One of this is the need for power and spectrally efficient modulation schemes to meet the spectral requirements of mobile communications. Linear modulation methods such as Quadarture Amplitude Modulation (QAM), Quadrature Phase Shift Keying (QPSK) and Orthogonal Quadrature Phase Shift Keying (OQPSK) have received much attention to their inherent high spectral efficiency. However for the efficient amplification of transmitted signal, the Radio Frequency Amplifier (RFA) is normally operated near the saturation region and therefore exhibit nonlinear behavior. As a result significant spectral spreading occurs, when a signal with large envelope variations propagates through such an amplifier and creates large envelope fluctuations. Pulse shaping plays a crucial role in spectral shaping in the modern wireless communication to reduce the spectral bandwidth.

The applications of signal processing techniques to wireless communication is an emerging area that has recently achieved dramatic improvement in results and holds the potential for even greater results in the future as an increasing number of researchers from the signal processing and communication areas participate in this expanding field (Grant, 1992; Iniaco and Embres, 1996; Piedra and Frish, 1996; Stevens, 1998; and Giannkis, 1999). From an industrial viewpoint also, the advanced signal processing technology cannot only dramatically increase the wireless system capacity but can also improve the communication quality including the reduction of all types of interference. As an example, a recent field test by Lucent Technologies demonstrated that adaptive signal processing for antenna arrays can be effectively used in mobile communication systems to mitigate the co-channel interference and increase the system capacity, setting a milestone for signal processing in wireless communications (Ojanpera and Prasad, 1998; Adachi, 2001; and Holma and Toskala, 2002) (http://www.umtsworld.com/technology/cdmabasics.htm and http:/sabyasachi.tripod.com/publications/3Gdata.pdf). Researchers are continuing their ideas for the development of an undefined wireless world, which could become operational by 2010 (Adachi, 2001). The next generation systems based on the Discrete Sequence Code Division Multiple Access (DS-CDMA), Frequency Division Multiple Access (FDMA)/Time Division Multiple Access (TDMA) and Global Systems for Mobile Communication (GSM) concepts are projected to provide transmitting high speed data, video and multimedia traffic for both indoor and outdoor systems, new technologies like Wideband Code Division Multiple Access (WCDMA), already in service, are providing users with high data rate services options like they have not experienced previously.

Telecommunications Journal, Pulse Shaping, Modern Wireless Communication, 3G Mobile Radio Systems, Wideband Code Division Multiple Access, 3G Mobile Communication, Universal Mobile Telecommunication System, Quadarture Amplitude Modulation, Signal Processing Techniques, Frequency Division Multiple Access, Code Division Multiple Access, Intersymbol Interference, Spectral Processing Technique, Fast Fourier Transform.