The advent of modern wireless devices, such as smart phones and MID1 terminals,
has revolutionized the way people think of personal connectivity. Such devices
encompass multiple applications ranging from voice and video to high-speed data
transfer via wireless networks. The voracious appetite of twenty-first century users
for supporting more wireless applications on a single device is ever increasing.
These devices employ multiple radios and modems that cover multiple frequency
bands and multiple standards with a manifold of wireless applications often running
simultaneously. This insatiable requirement for multistandard multimode devices
has ushered in new innovations in wireless transceiver designs and technologies
that led and will continue to lead the way to highly integrated radio solutions in
the form of SoCs.2 These solutions include several radios and digital modems all
designed on a single chip.
The design of such futuristic wireless radios and modems, capable of supporting
multiple standards and modes, is drastically different from traditional designs supporting
a single standard. The complications stem due to the high level of integration,
low power, and low cost requirements imposed on the chip manufacturers.
Until recently, most designers and architects designed for one particular application
or another, which in turn meant familiarity with certain modem or radio architecture
targeted for a certain wireless standard. However, designing future wireless devices,
which entail designing for multimode and multistandard wireless applications, will
require the radio engineer to be familiar with all facets and nuances of various transceiver
architectures. This in essence will help maximize the efficiency of the design,
lower the overall cost of the device, and allow for coexistence and simultaneous
operations of various radio.
