Due to increasing demand for video signal processing and transmission of high speed and higher order, Finite Impulse Response (FIR) filters have frequently been applied for performing adaptive pulse shaping and signal equalization of received data in real time. Pulse shaping for wireless communication over time as well as frequency selective channels is the need of the hour for 3G and 4G systems. Due to intensive use of digital filters in video and communication systems, high performance in speed, area and power consumption is demanded. With the recent exploding research interest in wireless communications, the application of signal processing to this area is becoming increasingly important. Indeed, the advances in signal processing technology make the most of today's wireless communications possible and hold the key to future services. The present paper deals with simulation model of square root raised cosine pulse shaping filter for Wideband Code Division Multiple Access (WCDMA) with different parameters of the filter at 5 MHz.

The application of signal processing techniques to wireless communications 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 can not only dramatically increase the wireless system capacity but also improve the communication quality, including the reduction of all types of interference. In this system, the user information bits are spread over a much wider bandwidth by multiplying the user data bits with quasi random bits, called chips, derived from CDMA spreading codes. In order to support very high bit rates (up to 2 Mbps), the use of variable spreading factor and multimode connection is supported. The chip rate of 3.84 Mcps is used to lead a carrier bandwidth of 5 MHz. Wideband Code Division Multiple Access (WCDMA) also supports high user data rates and increased multipath diversity (Ken, 2002). Here, each user is allocated the frames of 10 ms duration during which the user data is kept constant though data capacity among users can change from frame to frame to satisfy the demand of higher data rates. This enables several users to transmit their information over the same channel bandwidth. This is the main concept of a WCDMA communication system.

The rapidly increasing popularity of mobile radio services has created a series of technological challenges. One of which is the need for power and spectrally efficient modulation schemes to meet the spectral requirements of mobile communications. Linear modulation methods, such as QAM, QPSK, OQPSK have received much attention due to their inherent high spectral efficiency. However, for the efficient amplification of transmitted signal, the radio frequency amplifier is normally operated near the saturation region and therefore exhibits a 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.

Information Technology Journal, FIR Filter, Simulation Model, Wideband Code Division Multiple Access, WCDMA, Pulse Family, QAM, QPSK, OQPSK, Communication System, Transmitted Signal, Radio Frequency Amplifier, Spectral Spreading, Mobile Radio Services, CDMA, Intersymbol Interference.