Quantance approach is unique in the industry.

The Quantance patent pending technology uses several innovations to significantly improve the efficiency of RF transmit circuits in wireless phones, data cards, or other mobile wireless products. First, using closed loop feedback, Quantance technology proactively drives the voltage level at the PA to track the RF signal modulation envelope in real time to operate the PA in saturation mode.  Second, this quickly changing supply voltage is produced by an efficient, low noise, ultra fast, power converter that is integral to the Quantance solution.  Third, in close coordination with the ultra fast power converter, signals from the RF output of the PA are fed back to RF correction circuitry within the Quantance design to eliminate distortions to ensure the RF signal output from the PA is linear.

This overall approach is compatible with polar techniques, but is not a polar modulation scheme.  In contrast, it is a unique approach utilizing both supply voltage and RF closed loop-feedback to operate the PA in saturation mode to maximize the efficiency of the PA and maintain RF signal integrity.

Proprietary supply voltage modulation technique

Quantance technology converts voltage from the battery and delivers it to the PA using a proprietary method centered around a high efficiency, high bandwidth, low noise, ultra fast power converter that delivers a precisely controlled, constantly changing, voltage to the PA’s supply voltage pin.  This voltage follows the path of the input data signal to instantaneously deliver the precise voltage necessary to optimize the efficiency of the PA for the signal at that moment.  This approach is applied in real-time, adjusting continuously throughout the period of the RF input.

This is very different than the more common approaches of providing a fixed voltage at a level higher than the actual voltage needed, or "envelope" techniques that follow a shape similar to the RF signal. The difference between the voltage level of these other techniques and the Quantance modulated voltage level reduces the battery current and significantly improves the PA efficiency. This enables the same or more RF signal power out of the PA with less battery power needed and at the same time reduces the junction temperature of the PA.

Amplitude and phase correction loops

Modulating the voltage input to the PA can create noise or other distortions in the amplified signal. To eliminate this, Quantance technology utilizes a closed-loop correction system containing very high bandwidth amplitude and phase loops to intelligently sense the RF signal amplitude and phase at the input and output of the PA, and applies a correcting signal to the RF signal path as it passes through the Quantance circuitry on its way to the input of the PA.  This cleans up any distortions introduced by the modulated voltage, the PA, surrounding circuitry, or operating conditions.  The closed loop circuitry is designed to use very little power, so the added energy necessary to implement Quantance technology is negligible.

Improved transmit power, improved efficiency, and reduced current.

Quantance technology substantially improves the linearity and efficiency of transmit PAs used in mobile phones and data cards, allowing the PA to operate at or near its saturation point, enabling more power at typical current levels, or the same power at significantly reduced current levels compared to common PAs.  This efficiency  enables the transmit circuit to deliver high power even with high peak-to-average ratio (PAR) modulation such as HSDPA and HSUPA and the next generation communication schemes, like LTE and WiMAX, where normally the PA would have to be operated with a substantial RF power back-off.

And there are many benefits beyond improved power, efficiency, and temperature reduction.  For a more complete listing of benefits, refer to the BENEFITS section and for a discussion of performance, refer to the PRODUCTS section.

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