09-11-2012, 01:33 PM
A SOFTWARE RE-CONFIGURABLE ARCHITECTURE FOR 3G AND WIRELESS SYSTEMS
A SOFTWARE RE-CONFIGURABLE.ppt (Size: 915 KB / Downloads: 37)
Mobile and wireless communications
Current generation wireless technology requires:
the use of different terminals
dedicated applications for each standard
Next generation software radio technology will provide:
the use of a single terminal
integrated applications for the different standards
3G and Wireless-LAN scenario.
WLAN services offer new business opportunities to service providers, and a comprehensive solution with GPRS and UMTS networks would provide users with flexibility and portability.
The standards currently in the market are GPRS, IEEE802.11/b and Bluetooth.
Third generation standards (UMTS and IEEE802.11/a) will provide high data rate radio access and they will allow new and more complex services.
From a digital point of view, the complexity of re-configurable systems will depend on the possibility to implement an appropriate software library. The reprogramming ability of the hardware platform (i.e. DSP/FPGA) will guarantee the system re-configuration.
Software Radio terminals
The software radio terminals must be auto re-configurable, in order to match the different telecommunication standards.
Software Radio (SWR) defines a radio system capable to change its radio parameters by software rather than by hardware, such as:
operating frequency range
bandwidth
level of power
type of modulation
channel coding
ecc..
Powerful Digital Signal Processors are needed to implement the demanded re-configurability
Ideal Software Radio system
Software Radio Transceiver, in its widest meaning, defines a general TX/RX architecture directly operating on an RF digitized information stream, which can be completely reconfigured by software.
The Analog to Digital conversion (ADC) is moved as near as possible to the antenna.
SWR capability to support different standards is mainly due to:
The range of frequencies and bandwidth of the RF stage;
The greatest bandwidth assigned to a signal;
The sampling frequency of the ADCs;
The maximum dynamic range;
The computational capability of the digital processors (DSP in general, and FPGA).