Tuning Solutions

Paratek produces RF tuning solutions for wireless handhelds. The baseline technology is a device called a Passive Tunable Integrated Circuit (PTIC), which has the unique ability to change capacitance upon a change in voltage. PTICs are thus able to positively effect antenna impedance, making handset perform exceptionally well under all operating conditions and essentially giving them the ability to self-tune!. Paratek's PTICs are fundamental to two different approaches to RF tuning for wireless handsets: Open-loop and closed-loop.

OPEN-LOOP: An open-loop product solution strives to improve the impedance at the antenna by taking instructions from the handset to modify the capacitance of the PTICs. For example, a change in slider or flip position would effect a certain state for the PTICs. So too would the presence of audio in the earpiece, a switch to a differend band, or a change in temperature. These and other 'state-changing variables' could be used to implement particular PTIC settings for best performance. Paratek's open-loop product is called the Radio Antenna Frequency Tuner (RAFT™), which comprises an integrated array of PTICs combined with an HV-DAC that sets and manages the bias voltages. RAFT is designed to optimize metrics such as Total Radiated Power (TRP) and Total Isotropic Sensitivity (TIS) in the handset. With such a circuit in place, even the smallest, thinnest antennas can be made to perform better and across multiple bands!

CLOSED-LOOP: A closed-loop solution essentially does the same task as the open-loop design, but adds sense and control features that continually monitor antenna impedance. The circuit adaptively instructs PTICs to change capacitance when impedance above or below a set value (normally 50 Ohms) is detected. Paratek's Adaptive Impedance Matching Module (AIMM™) is an example of a closed-loop solution. Like RAFT, AIMM is an integrated multi-chip-module (MCM) product that combines an array of PTICs with the HV-DAC that sets and manages the bias voltages. AIMM adds algorithms embedded within the sense and control feature to continually monitor impedance. The simple act of holding a phone next to your head, or opening the flip/slide, can worsen antenna impedance. This results in a poorly-performing power amplifier (PA), and users would see this in the form of shorter battery life, reduced talk time, and dropped or missed calls. With AIMM in place, the entire mobile handset operates and performs more efficiently, giving customers a very positive user experience!