摘要:
A system and method of amplitude modulation is described in which first and second 180 degrees out-of-phase signals are produced and are each amplified by one of two (different amplification factor) non-linear amplifiers. One of the signals is amplified using constant amplification by a first non-linear amplifier to generate a relatively small amplified signal. The other of the signals is modulated using variable amplification by a second non-linear amplifier to generate a relatively larger amplitude modulated signal. The two resulting 180 degree out-of-phase signals are combined, such that the smaller signal effectively cancels out lower level distortion exhibited by the larger amplitude modulated signal. Alternatively, a symmetrical structure can be used for generating AM signals which include phase reversals of the carrier.
摘要:
This invention controls and modulates switched-mode power amplifiers to enable the production of signals that include amplitude modulation (and possibly, but not necessarily, phase modulation), the average power of which may be controlled over a potentially wide range.
摘要:
This invention controls and modulates switched-mode power amplifiers to enable the production of signals that include amplitude modulation (and possibly, but not necessarily, phase modulation), the average power of which may be controlled over a potentially wide range.
摘要:
This invention controls and modulates switched-mode power amplifiers to enable the production of signals that include amplitude modulation (and possibly, but not necessarily, phase modulation), the average power of which may be controlled over a potentially wide range.
摘要:
The present invention, generally speaking, provides for true multi-mode operation enabling mode switching to be done on-the-fly, in real time. Ramping techniques are provided to fully ramp a communications signal down and then back up inside a guard period while switching from one mode to another so that signal glitches occur only while the signal is ramped down and so can be made negligible. In another aspect of the invention, an advantageous multi-mode communications platform having a polar modulation architecture is provided. Preferably, the platform is based on a multi-mode, predominantly digital, single-chip communications signal processor. A digital, phase-stable, frequency lock loop enables versatile, low-power operation.
摘要:
This invention controls and modulates switched-mode power amplifiers to enable the production of signals that include amplitude modulation (and possibly, but not necessarily, phase modulation), the average power of which may be controlled over a potentially wide range.
摘要:
A first amplified signal is produced at a first amplifier, a second amplified signal is produced at a second amplifier, and a differential signal representing difference between the first amplified signal and the second amplified signal is generated at a subtraction unit receiving the first amplified signal and second amplified signal, the differential signal being a final amplified signal having a final modulated amplitude and a final modulated phase.
摘要:
This invention controls and modulates switched-mode power amplifiers to enable the production of signals that include amplitude modulation (and possibly, but not necessarily, phase modulation), the average power of which may be controlled over a potentially wide range.
摘要:
This invention controls and modulates switched-mode power amplifiers to enable the production of signals that include amplitude modulation (and possibly, but not necessarily, phase modulation), the average power of which may be controlled over a potentially wide range.
摘要:
Methods and apparatus for activating a purchased or previously deployed device by a subscriber. In one embodiment, activation includes authenticating the device to a service provider or carrier, and providing the device with data necessary for enabling the service to the device. In one variant, a user device is activated at a retail store, with the assistance of a carrier representative. In another variant, user equipment is activated via a communications network without the assistance of a representative. In yet another variant, the user equipment is activated via the Internet without the assistance of a representative. The provision of access data includes pre-assigning eSIM from a population of unassigned eSIMs to certain devices for various carrier networks. Alternatively, the eSIM may be assigned on an as-needed basis. Unassigned and/or unused eSIMs can be released (or sold back to the vendor) and/or reused. Solutions for eSIM backup and restoration are also described.