ET is now becoming a mainstream feature of 4G smartphones such as Apple’s iPhone 6, the Samsung Galaxy S5, and dozens of other models from leading OEMs like HTC, Sony and Amazon, with more than 125 million ET-enabled smartphones forecast to ship during 2014.
As wireless technology moves towards LTE-Advanced and 5G, the need for ET becomes even greater.
Benefits of ET for smartphones
- Longer battery life
- Reduced heat dissipation
- Better coverage
- Increased transmit power
- Higher data rates
- Reduced peak current
- Improved performance under antenna mismatch
- Enables broadband PAs supporting more frequency bands
- Simplifies or eliminates the need for DPD
Longer battery life
The RF Power Amplifier in a 4G smartphone is one of the most power-hungry components in the phone, consuming around 1.5 watts during transmit bursts.
Nujira’s ET chips cut PA energy consumption by 30%-40%, extending smartphone battery life, and allowing OEMs to reduce battery capacity for smaller, thinner and cheaper products.
Reduced heat dissipation
Nujira’s ET chips cut PA heat dissipation by up to 80%, significantly reducing the operating temperature and enabling smaller, thinner form factors.
Most of today’s 4G smartphones don’t transmit at the full power allowed by the standard, often backing off by up to 50% at high data rates.
Nujira’s ET chips boost the peak output power of the PA beyond the battery voltage, enabling full bandwidth transmissions even deep inside buildings, or at the edge of the cell.
The result for users is better coverage, fewer dropped calls and higher data rates. Network operators also benefit from the increased spectrum efficiency and cell capacity of a full power handset.
Improved performance under antenna mismatch
With an increasing number of frequency bands packed into a smaller space, antenna performance suffers.
Unlike traditional PAs, where linearity degrades rapidly with antenna mismatch, Nujira’s patented IsoGain ET operation maintains signal quality even into a severe mismatch, giving better coverage and helping to avoid “AntennaGate” incidents.
For a more detailed explanation, read our technical white paper.
Reduced peak current
The bursty nature of 4G transmissions results in significant spikes of current during transmit bursts, with 400-500 mA being drawn from the battery. During these spikes, battery voltage can drop significantly, causing “brownouts” in other parts of the system.
With other system components such as multi-core Application Processors and large, vivid colour displays all competing for the limited peak current capability of the battery, managing peak currents can be as important for the product designer as overall battery life.
Nujira’s ET chips cut peak current consumption during transmit bursts by 30-40%, relieving the load and allowing use of a smaller, cheaper battery.
Enables more frequency bands
With the latest smartphones supporting up to 20 LTE bands, Multi-Mode, Multi-Band PAs are now required to minimise cost and size, but introduce an additional energy efficiency penalty due to the wideband match.
Nujira’s wide swing-range ET chips boost the supply voltage to the PA, making it easier to achieve a broadband match, and overcoming the efficiency penalty of multi-band PAs.
Simplifies or eliminates the need for DPD
Nujira’s patented IsoGain® ET shaping table approach, combined with our high bandwidth, high swing range ETICs allows the linearization of the PA can be dramatically simplified, or eliminated altogether.
By operating the PA in ET mode, variations over temperature and mismatch are significantly reduced, eliminating the need for power-hungry closed loop adaptive DPD.
This simplifies the product development cycle, speeds time-to-market, and reduces cost and power consumption in the modem IC.