Patent application number | Description | Published |
20090072927 | TUNEABLE BANDPASS FILTER - A tuneable bandpass filter comprising a plurality of coupled resonators, the filter comprising
| 03-19-2009 |
20090231056 | Band Combining Filter - A band combining filter for passing signals in a communications band includes a plurality of cascaded directional filters. Each directional filter has at least two inputs and at least two outputs. The nth directional filter is arranged such that output signals O | 09-17-2009 |
20090302939 | POWER AMPLIFIER WITH DIGITAL PRE-DISTORTION - A power amplifier using a digitally pre-distorted compound semiconductor transistor is discussed. The amplifier has improved linearity. For a given gate bias voltage, there exists a drain voltage at which the drain current is the same for a pulsed signal as for a DC signal and is invariant to quiescent bias points occurring when a pulsed signal is applied. If an amplifier operates at this point, the trapping effects that lead to memory effects do not affect the dynamic behaviour of a digitally pre-distorted amplifier, resulting in improved linearity. The existence of this point, and it's benefits to the linearity of a digitally pre-distorted amplifier, have not been previously recognised. | 12-10-2009 |
20110001585 | TUNEABLE FILTER AND A METHOD OF TUNING SUCH A FILTER - A tuneable filter comprising a filter body defining a tuning cavity; a tuning member within the tuning cavity; and, a linear actuator adapted to displace the tuning member within the cavity to tune the filter; the linear actuator comprising a motor; a drive arm connected to the motor and extending along a drive axis, the drive arm being adapted to be rotated about the drive axis by the motor; an extension arm extending along the drive axis being connected at one end to the tuning member and being in engagement with the drive arm at the other end; the engagement between the drive arm and extension arm being arranged such that rotation of the drive arm about the drive axis displaces the extension arm along the drive axis; each of the drive arm and extension arm comprising an end stop, the end stops being arranged such that as the extension arm reaches the end of its range of travel towards the drive arm the drive arm end stop rotates into abutment with the extension arm end stop, preventing further rotation of the drive arm. | 01-06-2011 |
20110115577 | LINEAR ACTUATOR - A linear actuator includes a drive arm and an extension arm each extending along a common drive axis. One of the arms has a plurality of resiliently deformable fingers extending beyond the end of the arm towards the other arm. At least one of the fingers has a thread on its inner face while the other arm has a threaded portion. At least part of the threaded portion is received between the fingers. The fingers are adapted to urge the threads of the two arms into interengagement such that rotation of the drive arm about the drive axis displaces the extension arm along the drive axis. The two threads are arranged such that when the ridge of one thread is received in the groove of the other thread the two sides of the ridge abut the two edges of the mouth of the groove. | 05-19-2011 |
20120229229 | Microwave Transmission Assembly - According to one or more embodiments, a directional filter assembly ( | 09-13-2012 |
20120293275 | ELECTRICAL FILTER - An electrical filter for filtering an electrical signal, the filter having a transmission characteristic comprising a band edge at a band edge transition frequency, the filter comprising a circulator having a first circulator port for receiving a signal to be filtered, the circulator being adapted to transfer a signal received at the first circulator port to a second circulator port and being further adapted to transfer a signal received at the second circulator port to a third circulator port; and, a reflection mode filter connected to the second port; the reflection mode filter comprising a filter network comprising at least one resonator, the filter network having a network input connected to the second circulator port; and, a further resonator connected to the network input, the further resonator being arranged to provide an extracted pole providing a transmission zero closest to the band edge transition frequency; wherein the further resonator has a high Q compared to the low Q of at least one of the at least one resonator of the filter network. | 11-22-2012 |
20120306590 | Band Combining Filter - A band combining filter for filtering a microwave signal having at least one band edge at a band edge transition frequency. The filter comprises a plurality of filter sections. Each filter section comprising 3dB hybrid couplers having input ports and output ports and resonators connected between the input ports and the output ports of the couplers. | 12-06-2012 |
20120306596 | Microwave Filter - A microwave filter for filtering a microwave signal is disclosed. The microwave filter has at least one band edge at a band edge transition frequency. The filter comprises an input port and an output port. The filter also comprises a plurality of single resonators connected in parallel between the input and output ports. The filter further comprises a frequency independent electrical coupling between the input and output ports connected in parallel with the resonators. A subset of the resonators has Q values each of which are at least a factor of three higher than the Qs of each of the remaining resonators. | 12-06-2012 |
20120309458 | MICROWAVE TRANSMISSION ASSEMBLY - A microwave transmission assembly comprising a combiner comprising first and second input ports and internal and external output a ports; the combiner being adapted to transfer a signal received at microwave frequency f | 12-06-2012 |