Abstract:
The present disclosure generally relates to any device capable of wireless communication, such as a mobile telephone or wearable device, having one or more antennas. After measuring reflection coefficients of a device at three different DVC states, the reflection coefficient for all other DVC states can be calculated. Thus, based solely upon three reflection coefficient measurements, the antenna can be tuned to adjust for any changes in impedance at the antenna.
Abstract:
The present disclosure generally relates to a device having a capacitance sensor that detects a change in capacitance that occurs in the antenna whenever the antenna is in close proximity to a user's hand and/or head. Following detection of the capacitance change, the capacitance of the antenna may be changed by using a variable capacitor that is coupled to the sensor through a controller.
Abstract:
The present disclosure generally relates to a device having a capacitance sensor that detects a change in capacitance that occurs in the antenna whenever the antenna is in close proximity to a user's hand and/or head. Following detection of the capacitance change, the capacitance of the antenna may be changed by using a variable capacitor that is coupled to the sensor through a controller.
Abstract:
The present disclosure generally relates to any device capable of wireless communication, such as a mobile telephone or wearable device, having one or more antennas. By applying a variable reactance (capacitive or inductive component) antenna aperture tuner within a simple, scalar antenna aperture tuning system, the maintenance of a constant antenna resonant frequency in the presence of environmental changes or head/hand effects is obtained. The variable reactance is used to adjust the resonant frequency of the antenna to stay at the desired target frequency in response to external variables that would otherwise shift the resonance away from the operating frequency of the device. Adjusting the resonant frequency of the antenna in response to externally induced changes maintains the radiating efficiency of the antenna and simultaneously avoids impedance mismatch between the antenna and the respective transmit/receive path in the radio, thereby minimizing transmission losses.
Abstract:
Embodiments disclosed herein generally relate to power amplifier matching circuits used for matching impedance and harmonic control in a device, such as a cellular phone. In one example, a power amplifier matching circuit includes two DVCs, four inductors, a transistor, and a capacitor. Utilizing the two DVCs, the impedance matching ratio and the center frequency of the circuit are capable of adjustment as needed. Moreover, the inclusion of the two DVCs may also prevent harmonic frequencies from undesirably passing through the power amplifier matching circuit to the antenna of a cellular device. The power amplifier matching circuit may be used in conjunction with an amplifier, where the output of the amplifier is proportional to the current in the circuit.
Abstract:
The present disclosure generally relates to a device having a variable frequency filter that rejects harmonics generated by a variable reactance device. The variable frequency filter may be coupled to the antenna and the variable reactance device. The filter includes a variable capacitor and an inductor coupled together as a resonant circuit. The filter may be used in cellular technology to prevent harmonic frequencies that are created by another variable reactance device from reaching the antenna of the cellular device. Furthermore, the filter can reflect any receiving frequencies from the antenna and prevent the receiving frequencies from passing through.
Abstract:
The present disclosure generally relates to the combination of MEMS intrinsic technology with specifically designed solid state ESD protection circuits in state of the art solid state technology for RF applications. Using ESD protection in MEMS devices has some level of complexity in the integration which can be seen by some as a disadvantage. However, the net benefits in the level of overall performance for insertion loss, isolation and linearity outweighs the disadvantages.