Microwave Journal
www.microwavejournal.com/articles/7171-nujira-expands-4g-handset-development-team

Nujira Expands 4G Handset Development Team

November 3, 2008

Nujira has expanded its development team focused on bringing to market a Coolteq™ solution to address the ballooning cost, size and power consumption of 4G handset RF front ends. As vice president of handset development, Julian Hildersley will lead a team that includes Martin Wilson, chief scientist and founder, and Bob Henshaw, who has joined the company as director, handset systems engineering. They are working with a team of three newly recruited IC design engineers with RF and analog development experience. As a consequence, Nujira has leased additional development laboratory floor space to accommodate the new staff at its Cambridge headquarters in the UK.

Commenting, Tim Haynes, the company’s CEO, said, “The RF challenge in a 4G multi-standard handset is the creation of a broadband network air interface that will work around the world within the size, power and cost constraints of a compact portable device. Nujira Coolteq technology has improved transmission efficiency in base stations from typically low 20 percent for a class AB amplifier to mid 40 percent. Internal evaluations show that similar performance can be achieved in the handset environment, and our expanded team has the resources to bring this technology to market in a production-ready form.”

Hildersley added, “So far, ten different FDD frequency bands and four different TDD frequency bands have been defined in 3GPP that can be used for LTE, and it is likely that more bands will be added to this list such as 700 MHz in the US. For 4G handset RF designers, the hurdle is the availability of efficient, wideband power amplifiers to support a high performance, cost-effective transmission circuit that works across all the frequency bands in use around the world. Conventional techniques for improving PA efficiency are inherently narrowband, and are unable to span more than a single band. This implies five or more conventional PAs for a broadband cellular RF interface seeking to cover all ten LTE bands – adding several dollars to the bill of materials. This additional cost of multi-banding maybe be halved if this could be reduced to one or two wide band PA devices without compromising efficiency. Applying Coolteq High Accuracy Tracking (HAT™) technology alongside current state of the art PA devices allows this to be achieved.”