PXI serves cell-phone alignment chores

The alignment phase is becoming increasingly complex for multimode and multiband phones. A test system must provide tuning adjustment to various receiver and transmitter subsystems to offset the effects of level linearity and frequency response in each of the bands supported.

A PXI-based signal analyzer for measuring RF power and transmitter characteristics can replace spectrum analyzers, power meters, and radio test sets.

Many types of instruments can be deployed at this stage. Your choice will depend on factors such as speed, accuracy, reliability, flexibility, and price. Stand-alone GPIB-controlled instruments have traditionally been the first choice, but newer bus technologies offer faster control speeds and data throughput.

Modular instruments such as VXI and PXI allow customized and reconfigurable RF test-systems that can interface with other system architectures, including GPIB. Of these two modular architectures, PXI offers higher bus speed at a lower price. An eight-slot PXI chassis comprising an embedded system controller, an RF signal generator with a dual-channel arbitrary waveform generator, an RF digitizer, and DUT interfacing can fulfill all of the alignment and characterization functions traditionally performed by rack-and-stack instruments but at a fraction of the cost.

For details on how to implement such a PXI-based alignment system, see the complete online version of this article at www.tmworld.com/pxi-rf.