Implementation Alternatives for a Flexible Wireless LAN Transceiver

1 Abstract In our software-defined radio project we have implemented two different types of standards, a continuousphase-modulation (CPM) based standard, Bluetooth, and an OFDM based standard, HiperLAN/2, on a generalpurpose processor. First we describe our baseband software-defined radio testbed for the physical layer of wireless LAN standards. All physical layer functions have been successfully mapped on a Pentium 4 processor that performs these functions in real-time. The testbed consists of a transmitter PC with a DAC board and a receiver PC with an ADC board. Channel selection functionality is performed at the DAC and ADC board, whereas all modulation and demodulation functions are mapped on software running on the CPU. Then, three implementation alternatives for the digital part of the transceiver are introduced. These include: • the testbed: a PCI card equipped with analog front-end functionality. All demodulation functions are performed in software running on the CPU of the notebook. • integration of analog front-end functionality in the chipset of the motherboard and demodulation functions are performed by the processor. • a low power DSP plus analog front-end functionality mounted on a PCI card. The alternatives are evaluated with respect to computational-power requirements, power consumption and expected manufacturing costs.