摘要:
An antenna is set in an antenna mounting of size and shape such that the antenna may be accommodated at least in part in the naturally occurring dip between a persons shoulder blades at the upper part of the back. The mounting includes supporting straps which extend during use from that part of the mounting hosting the antenna, over the shoulders of the wearer and down the front of the wearers torso. The antenna mounting is provided in a garment (not shown) suitable for wearing about the upper part of the body. By extending the support straps over the wearers shoulders in this way, the weight of the straps serves to counter balance the weight of the antenna and mounting to provide more even weight distribution of the antenna and mounting combined between the front and back of the wearer, so as to be centered about the wearers shoulders. Such weight distribution seeks to improve the comfort of a garment provided with the antenna and mounting and will generally contribute to the correct ‘hang’ of the garment itself. In one arrangement the antenna is a fabric patch antenna.
摘要:
A capacitively back-coupled wireless terminal (10) comprises a PCB (22) having a ground conductor (24) on one surface. A back coupling capacitor (C) is carried by the ground conductor. An elongate slot (30) is provided in the ground conductor to widen the bandwidth. An electromagnetic shield (32) is provided on the side of the PCB (22) which in use is facing a lossy dielectric in order to reduce the SAR. The shield is disposed adjacent to, but spaced from, the slot (30) in the ground conductor and the back coupling capacitor. For narrowband operation the slot may be omitted and/or the spacing between the PCB (22) and the shield (32) may be reduced.
摘要:
A portable communication device has an antenna configuration that allows to form various different antenna directivity configurations. In particular, a control device discriminates between a transmitting state and a receiving state of the communication device. As based thereon, it effects various non-uniform selection patterns among the directivity configurations.
摘要:
A radio frequency suppressing cable has at least one conductor and a resistive layer surrounding the at least one conductor and insulated from the at least one conductor. The bulk resistance of material included in the resistive layer is greater than that of the material of the at least one conductor. In addition, the thickness of the resistive layer is greater than the skin depth &dgr; for the radio frequency, where δ = 1 π σ f μ r μ o where &sgr; is the conductivity of the material, f is the frequency, &mgr;r is the magnetic permeability relative to that of free space, and &mgr;o is the magnetic permeability of free space.
摘要:
A patch antenna (10) for mobile telecommunications use is designed for incorporation into the garment of a wearer, e.g. in a shoulder pad (10) or lapel (30). The antenna comprises first and second (12, 16) spaced layers of electrically conducting fabric with a layer (14) of insulating fabric between, and a connection between the conducting layers. The conducting layers (12, 16) may be a single strip of shaped fabric (A, B, C) folded around the insulating layers. The conducting layers are shaped so that the layer adjacent the wearer is of larger area and is connected as the ground plane of the antenna so as to shield the wearer from the strongest electrical fields. Also, the patch antenna is arranged so that its radiating regions (24, 38) are remote from the user's head.
摘要:
A method of matching a receive-only antenna (60) for use in receiving video signals in which measurements made on a transceiver's antenna (14) when in an transmitting mode are used in matching the receive-only antenna. The ratio of the amplitude of the reflected signal to the strength of the transmitted signal strength is used not only in selecting components for matching the transceiver's antenna (14) but also in selecting components for matching the receive-only antenna (60). The ratio may be applied to respective look-up tables (54, 64) for selecting the components to be used in matching the respective antennas.
摘要:
A connector device is provided in the form of a main body component having a lower surface covered with a conductive layer to provide a ground plane and an upper surface carrying a conductive strip portion to form a microstrip line. The combination of the first conductive surface region (ground plane) and second conductive surface region (microstrip line) separated by the main body component dielectric forms a microstrip section. The conductive layer and strip portion are each connected to a conductor of co-axial feed cable. The device is inserted between conductive layers of an antenna of laminar construction, such a as planar inverted F antenna to establish electrical connection between conductors of the feed cable and conduction layers of the antenna. The connector is secured to the antenna by sewing or adhesive. The antenna is normally positioned in a garment.
摘要:
A communications device comprises a loop antenna having a plurality of feed terminals defining at least two terminal pairs. A controller is provided for selecting one terminal pair to enable reception or transmission from the loop antenna using the selected terminal pair. The selection of terminal pair is made based on the measurement of at least one parameter which is responsive to the proximity to the antenna of, for example, a user of the device. One terminal pair provides an antenna having matched impedance when the user is near the device, and the other terminal pair provides an antenna having matched impedance when the user is distant.
摘要:
A wireless terminal a transceiver coupled to an antenna feed and a ground conductor (502), the antenna feed being coupled directly to the ground conductor (502). In one embodiment the ground conductor is a conducting case (902). The coupling is via a parallel plate capacitor formed by a respective plate (506) and a portion of the surface of the case (502). The case (502) acts as an efficient, wideband radiator, eliminating the need for separate antennas. Slots (912, 1214) perform a matching function, eliminating the need for matching between the transceiver and antenna feed.
摘要:
A horn antenna arrangement comprising an H-plane sectoral horn 19 in combination with a feeder waveguide 2 in which radio-frequency energy is launched and propagated in the fundamental rectangular waveguide TE(1,0) mode and provided with a mode-converting section 25 of suitably shaped waveguide of reduced height in which the fundamental TE(1,0) rectangular type mode in, e.g. a planar arcuate input cross section 26, is smoothly and gradually converted into the fundamental TM(0,1) mode of an H-plane sectoral horn in an output cross section 30 which is cylindrically curved about the z axis forming the central axis of sectoral flare for the horn 19, substantially without generating any higher horn modes.