05 Fakultät Informatik, Elektrotechnik und Informationstechnik
Permanent URI for this collectionhttps://elib.uni-stuttgart.de/handle/11682/6
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Item Open Access Design of radio frequency power amplifiers for cellular phones and base stations in modern mobile communication systems(2009) Wu, Lei; Berroth, Manfred (Prof. Dr.-Ing.)The mobile radio communication has begun with Guglielmo Marconi's and Alexander Popov's experiments with ship-to-shore communication in the 1890's. Land mobile radio telephone systems have been used since the Detroit City Police Department installed the first wireless communication system in 1921. Since that time, radio systems have become more and more important for both voice and data communication. The modern mobile communication systems are mainly designed in high frequency ranges due to the larger available bandwidth at these frequencies. Today, the mostly used mobile communication systems in the United States are cellular telephone systems operating at 800 - 900 MHz and personal communication systems (PCS) at 1800 - 2000 MHz. In Europe, these include the Global System for Mobile Communication (GSM) and Universal Mobile Telecommunications System (UMTS). China now has GSM/GPRS and Code Division Multiple Access (CDMA) networks. For the third generation services, China has been planning a 3G standard called Time Division Synchronous CDMA (TD-SCDMA) since 1999, which is planned to operate at 2010 MHz - 2025 MHz. In this work, attentions are paid on the uplink and downlink applications in the GSM and the UMTS systems adopted in Europe. No matter which system is discussed, a wireless communication link usually includes a transmitter, a receiver, and a channel. The functions of the quantization, of the coding and of the decoding are only performed in digital systems. Most links are fully duplex and include a transmitter and a receiver or a transceiver at each end of the link. Obviously, to send or receive large enough signals, power amplifiers and their driving amplifiers are necessary on both sides of the link. A radio frequency power amplifier is a circuit for converting directional current input power into a significant amount of RF output power. One of the principal differences between a small-signal amplifier design and a power amplifier design is that the main purpose of the latter is the maximum output power, not the maximum gain. However, a power amplifier cannot simply be regarded as a small-signal amplifier driven into the saturation. There is a great variety of different power amplifiers, while most of them employ techniques beyond simple linear amplification. In other words, RF power can be generated by a wide variety of techniques using a wide variety of devices. In this work, the fundamental theories used for the design of RF power amplifiers are systematically introduced. Using these theories, power amplifier circuits are designed both for the base stations and for the cellular phones adopted in the modern mobile communication systems in Europe.