摘要:
A frequency conversion circuit having a plurality of N signal channels, each being fed an input signal and a train of pluses having a period T and a duty cycle T/N. Each channel includes: a sampler coupled the input signal and being responsive to sampling signals; and a controllable time delay for producing the train of sampling signals in response to the train of pulses, the time delay imparting a time delay to the pulses in accordance with a time delay command signal fed to the time delay. Each one of the sampling signals is produced by the time delay in each one of the channels with the period T and the duty cycle T/N with the sampling signals in one of the to trains of the sampling signals being delayed with respect to the sampling signals in another one of the trains the sampling signals a time T/N.
摘要:
A method delaying a pulse domain signal using a time encoder circuit and a time encoder based beamformer method and apparatus for use in receiving and/or transmitting applications.
摘要:
A phased array transmitter is disclosed comprising a vector modulator, a true time delay block coupled to the vector modulator, a local oscillator phase shifter and RF-converter block coupled to the true time delay block, and an antenna. The vector modulator applies vector modulation to a baseband signal and provides an intermediate frequency signal to the true time delay block. The true time delay block applies a true time delay to the intermediate frequency signal and provides a delayed intermediate frequency signal to the local oscillator phase shifter and RF-converter block. The local oscillator phase shifter and RF-converter block multiplies the delayed intermediate frequency signal by a local oscillator signal and applies a phase shift to the delayed intermediate frequency signal to provide a radio frequency signal to the antenna for onwards transmission.
摘要:
The disclosed embodiments generally relate to techniques for processing signals received from multiple antennas. More specifically, the disclosed embodiments relate to a system that uses an integrated phase-shifting-and-combining circuit to process signals received from multiple antenna elements. This circuit applies a specified phase shift to the input signals, and combines the phase-shifted input signals to produce an output signal. In some embodiments, the integrated phase-shifting-and-combining circuit uses a current-steering mechanism to perform the phase-shifting-and-combining operations. This current-steering mechanism operates by converting the input signals into associated currents, and then steering each of the associated currents through multiple pathways which have different delays. Next, the currents from the multiple pathways for the associated currents are combined to produce the output signal. During this process, while steering each of the associated currents through multiple pathways to achieve different phase shifts, complementary impedance changes through the multiple pathways cause the aggregate impedance at the output to remain substantially constant.
摘要:
The present invention concerns a method for the formation of a desired electromagnetic pulse by using an array of antennae in the time domain, and a relevant modular apparatus for the transmission of electromagnetic pulses, wherein each module is provided with means adapted to realize a programmed synchronization of the array.
摘要:
A method of beamforming a radiofrequency array having multiple antenna elements is provided. The method includes transmitting two or more sub-beams of a modulated light beam through a switched fabric, using wavelength switching to designate a respective path through the switched fabric for each sub-beam, and converting each sub-beam to a driving signal for one or more of the antenna elements or to a received signal from one or more of the antenna elements. Each path through the switched fabric has a selected cumulative true time delay.
摘要:
A selectable beam antenna of generally linear, polygonal, planar or polyhedral form, able to operate at microwave and millimetre wave frequencies, and constructed from associated networks that incorporate radio frequency switches, time delays and amplitude weights positioned within a set of interleaved transmission, lines or waveguides to simultaneously perform both beam-forming and beam selection operations, which selectable beam antenna comprises: (i) a single RP antenna port connected to a 1-to-N corporate feed means, where N is greater than or equal to 2; (ii) a EF switch network means of N/q multi-pole-multi-throw radio frequency switch means (qPMT) connected to the corporate feed means; (iii) a RF distribution means of N×M singularly or multiply interleaved lines arranged so as to have approximately equal transmission length connected to the switch means, where M is the number of throws associated with each radio frequency switch means (qPMT); (iv) an antenna launch means of M×M interleaved antenna element sub-groups of S linear or planar elements, where S is greater than or equal to one, σorporately connected to the distribution means and arranged to closely follow at sub-wavelength intervals a closed are or segment of a closed surface; and (v) an overall electronic control means to set all radio frequency switches in such a way to select, to time delay and to amplitude weight the activated interleaved antenna launch elements and thus generate one of the possible directed, antenna beams.
摘要:
The invention is related to methods and apparatus for controlling and adapting a digital predistortion linearizer for amplification of bandlimited signals using non-linear amplifiers. The control method advantageously permits the predistortion function applied by a predistortion entity to provide a relatively constant gain. This attribute is advantageous for operation within cellular radio systems, which often employ digital power control systems. However, the disclosed techniques can also be applicable to virtually any type of digital predistortion for which an input signal or reference signal to be amplified is predistorted in a manner that is complementary to the distortion induced by a non-linear amplifier. Embodiments of the invention advantageously enhance the practicality of using digital linearization and predistortion amplification techniques. Embodiments of the invention can automatically adjust the characteristics of a predistorted signal so that a deviation from overall linearity is compensated and subsequently reduced while maintaining a nearly constant gain attribute.
摘要:
In order to make it possible to direct sufficient microwave energy at a target with an electronic device which is to be interfered with or to be destroyed, the beams (7) from at least two antenna arrays (10) are focused on an effective area (8) in the vicinity of that target, preferably from a vehicle (3) which is equipped with these arrays (10). For effective super-imposition of the emitted microwave energy (7) in the emission direction of in each case one of the arrays (10), the use of an arc for discharging the capacitance (43) of the resonator via its spark gap (13) is observed, and is recorded quasi-continuously optoelectronically. The electrode separation of the spark gap (13) or the fluid pressure of the dielectric in the vicinity of the spark gap (13) is then varied by control elements such that all of the spark gaps (13) in an array (10) ignite virtually at the same time, so that their discharge current pulses which lead to the emission of the microwave energy (7) start virtually in phase.
摘要:
A system for signal processing is provided. A sampling delay system generates a plurality of sampling delay values. A plurality of programmable delays each receives one of the sample delay values. A plurality of sample and hold units, each coupled to one of the programmable delays, generates a sample of a received signal in response to an input from the programmable delay.