1108 results about "Band notched" patented technology

This invention permits the upstream transmission of short packets of information in a cable TV system, and blocking upstream noise at all other times, and does so without interfering with image quality of normal TV viewing. A remotely operable ingress noise blocking filter is placed at the terminating junction between a subscriber's coaxial drop cable and a corresponding feeder tap in a cable TV system. The ingress noise blocking filter contains a high pass filter to pass the normal TV band. This high pass filter is bypassed by a section containing low pass filters and a switch operated when receiving a control signal from a cable modem during those short durations the cable modem is authorized to transmit an upstream signal. Low pass filters isolate the switching elements so that switching transients cannot occur in the downstream TV band. The level of the amplitude of the downstream signal is unaffected whether the switching elements are open or closed. Further, the switching arrangement provides a relatively constant impedance, both when the switching element is on and off to provide a high return loss and avoid signal reflections and maintain signal quality. In a diagnostic mode, the location of each noise source is determined by correlating the energy measured at each a set of frequencies across the band at the headend during those periods when the cable modem is allowed to transmit versus the energy received during those periods when the same cable modem is not authorized to transmit.

A Parasitic Element (202) for use in combination with a Planer Inverted “F” Antenna (PIFA) (100) that creates an additional band of efficient operation for the combined antenna structure (200). The parasitic element (202) is able to be made to conform to surfaces (704) that are near the PIFA, such as of a case (704) of a cellular telephone (706). The parasitic element (202) is positioned so as to radiantly couple with the PIFA (100) in order to create the additional band of efficient operation. A parasitic element (202) is used with a dual band PIFA that operates in two RF bands, such as in the region near 800 MHz and 1.9 GHz, and adds a third band such as in the region near 1.575 GHz to support reception of Global Positioning System signals. This parasitic element (202) can conform to a case (704) of the cellular telephone (706).

The present invention refers generally to a new family of antenna arrays that are able to operate simultaneously at two different frequency bands, while featuring dual-polarization at both bands. The design is suitable for applications where the two bands are centered at two frequencies f1 and f2 such that the ratio between the larger frequency (f2) to the smaller frequency (f1) is f2 / f1<1.5. The dual-band dual-polarization feature is achieved mainly by means of the physical position of the antenna elements within the array. Also, some particular antenna elements are newly disclosed to enhance the antenna performance.

A dual band full duplex mobile radio is provided that includes a transmit portion including a dual band filter and a receive portion including a dual band filter. The dual band full duplex mobile radio further includes a circulator connecting the transmit portion and the receive portion and configured to provide transmit and receive switching.

With an index that represents the content of a message, a communication band is assigned. At this point, communication bands are managed as fixed bands and variable bands. An index is used to secure a fixed band when the transmission a data flow corresponding to a communication request is started. In addition, an index is used to coordinate variable bands. Thus, priority levels of communication requests are objectively designated corresponding to the contents of communication requests and features of mediums. In the case that a fixed band and a variable band are secured, when a function for scheduling and reserving communication resources for communication requests is accomplished, priority levels are objectively designated with an index.