Nujira Ltd, a leading specialist in Envelope Tracking (ET) technology, has released its new “Woodstock” 16-band Multi-Mode, Multi-Band (MMMB) ET reference design for 4G smartphone RF Front Ends. Using the company’s recently unveiled NCT-L1200 ET chip, the reference design is able to overcome the energy efficiency and frequency band challenges that are faced by mobile operators and handset OEMs since the introduction of 4G. Covering up to 16 frequency bands from 700MHz to 2.7GHz in a PCB area of less than 200 mm2, the new ET reference design is able to provide state-of-the-art multi-band 2G, 3G and 4G performance, while using less PCB area and battery power than today’s 3G smartphones.
Mobile handset developers are currently faced with a number of RF engineering challenges. They need to simultaneously support different operating modes (e.g. LTE, TD-LTE, WCDMA, HSPA and GSM) in one handset, while also supporting an increasing number of frequency bands. At present LTE is deployed worldwide in 20 frequency bands from 700 MHz to 2.7 GHz, with each requiring a dedicated PA and RF filter.
With this discrete design approach, up to nine variants of some popular smartphone models are required to cover all regions and operators. This results in increased design and verification effort, numerous production runs, delayed product rollouts and a complicated, costly inventory management process.
With the Woodstock reference design, Nujira is able to provide a highly integrated solution for global 3G/4G terminals. Incorporating a multi-mode, multi-band ET Power Amplifier (PA), a broadband 2.3-2.7 GHz ET PA, and an additional region- or operator-specific LTE ET PA, the design ensures maximum frequency band coverage and energy efficiency at minimal costs. By enabling handsets to operate on almost all worldwide 3G and 4G bands, Nujira’s new reference design significantly reduces the need for numerous regional product variants.
The Woodstock design integrates Nujira’s NCT-L1200 Envelope Tracking supply modulator with PA devices, switches and filters from a number of Tier 1 suppliers, providing handset manufacturers with a complete solution from transceiver to antenna. Nujira’s ET modulator enables the handset to deliver full power to the antenna port, maximising coverage and boosting data rates, even for LTE signals with high Peak-to-Average Power Ratios (PAPR), eliminating the need for Maximum Power Reduction (MPR). The NCT-L1200 ETIC has the industry’s lowest output impedance, enabling it to drive up to 4 PA devices in parallel without compromising performance, even on the highest bandwidth 20 MHz LTE channels, while cutting energy consumption by 35%. The design also includes several patented PCB and component-level innovations to maximise system performance.
Nujira is also supplying a complete suite of MIPI RF Front End (RFFE) control scripts, ET shaping tables, and production calibration algorithms for the solution, minimizing time-to-market for platform vendors and OEMs.
Commenting Tim Haynes, CEO, Nujira said “Our new reference design provides vendors with a rapid solution for single-SKU global 4G handsets which can beat today’s 3G phones on cost, size, RF performance and power consumption. Adding Envelope Tracking to a couple of specific LTE bands is relatively straightforward, but doesn’t by itself solve the cost, footprint and power consumption challenges the industry is facing. What the mobile industry really needs is Multi-Mode, Multi-Band reference designs that can be quickly incorporated into handsets. MMMB front ends are undoubtedly the future, and Nujira’s reference design is the first result of our close collaboration with the world’s leading PA vendors to make ET MMMB RF front ends a commercial reality.”