Inventors list |
Assignees list |
Classification tree browser |
Top 100 Inventors |
Top 100 Assignees |
Aryan
Aryan Saed, Ottawa CA
| Patent application number | Description | Published |
|---|---|---|
| 20080268795 | PREDISTORTION CIRCUIT FOR A TRANSMIT SYSTEM - Systems and methods related to amplifier systems which use a predistortion subsystem to compensate for expected distortions in the system output signal. A signal processing subsystem receives an input signal and decomposes the input signal into multiple components. Each signal component is received by a predistortion subsystem which applies a predistortion modification to the component. The predistortion modification may be a phase modification, a magnitude modification, or a combination of both and is applied by adjusting the phase of the fragment. The predistorted component is then separately processed by the signal processing subsystem. The processing may take the form of phase modulation and amplification. The phase modulated and amplified components are then recombined to arrive at an amplitude and phase modulated and amplified output signal. The predistortion modification is applied to the components to compensate for distortions introduced in the signal by the signal processing subsystem. | 10-30-2008 |
| 20090279639 | DIGITAL BRANCH CALIBRATOR FOR AN RF TRANSMITTER - The present invention provides a digital (computational) branch calibrator which uses a feedback signal sensed from an RF transmit signal path following the combining stage of LINC circuitry of a transmitter to compensate for gain and phase imbalances occurring between branch fragment signals leading to the combiner. The calibrator feeds a quiet (zero) base band signal through the transmit path during the calibration sequence (i.e. a period when data is not transmitted) and adjusts the phase and gain of the phasor fragment signals input thereto by driving the sensed output power to zero. The calibration is performed by alternating phase and gain adjustments with predetermined (programmable) and multiple update parameters stages (speeds). A baseband modulation is preferably used to distinguish false leakage (e.g. due to local oscillator, LO, feed through and DC offset in the base band Tx) from imbalance leakage. | 11-12-2009 |
Aryan Saèd, Port Coquitlam CA
| Patent application number | Description | Published |
|---|---|---|
| 20080219340 | FREQUENCY DOMAIN EQUALIZER FOR WIRELESS COMMUNICATIONS SYSTEM - The present invention relates to wireless communications and is particularly applicable to devices and modules for correcting errors introduced to a wireless signal after its transmission. An equalizer is provided which compensates for undesirable effects on received radio signals introduced by either signal processing or by the transmission medium. In operation, the equalizer multiples the complex received signal with a complex corrective signal that compensates for these effects. A tap corrective signal corrects for time-varying channel effects (i.e. channel distortions), a timing tracking signal corrects for carrier frequency offset errors, and a phase tracking signal corrects for sampling frequency offset errors. | 09-11-2008 |
| 20100214018 | ADAPTIVE PREDISTORTION FOR A TRANSMIT SYSTEM - Systems, methods, and devices relating to the provision of deliberate predistortion to an input signal to compensate for distortions introduced by an amplifier subsystem. An input signal is received by a signal processing system which includes a predistortion subsystem. The input signal is decomposed and the fragments are then predistorted by the predistortion subsystem by applying a deliberate predistortion to the fragments. The predistorted fragments are then separately processed and recombined to arrive at the system output signal. The predistortion subsystem adaptively adjusts based on characteristics of the system output signal. Also, the predistortion subsystem is equipped with a control system that is state based—the state of the predistortion subsystem is dependent upon the prevailing conditions and, when required, the control system switches the state of the predistortion subsystem. A feedback signal, a replica of the system output signal, is used in updating lookup table entries used to determine the predistortion. | 08-26-2010 |
Aryan Saèd, Port Coquitlam CA
| Patent application number | Description | Published |
|---|---|---|
| 20100214018 | ADAPTIVE PREDISTORTION FOR A TRANSMIT SYSTEM - Systems, methods, and devices relating to the provision of deliberate predistortion to an input signal to compensate for distortions introduced by an amplifier subsystem. An input signal is received by a signal processing system which includes a predistortion subsystem. The input signal is decomposed and the fragments are then predistorted by the predistortion subsystem by applying a deliberate predistortion to the fragments. The predistorted fragments are then separately processed and recombined to arrive at the system output signal. The predistortion subsystem adaptively adjusts based on characteristics of the system output signal. Also, the predistortion subsystem is equipped with a control system that is state based—the state of the predistortion subsystem is dependent upon the prevailing conditions and, when required, the control system switches the state of the predistortion subsystem. A feedback signal, a replica of the system output signal, is used in updating lookup table entries used to determine the predistortion. | 08-26-2010 |