Abstract: Dynamically switchable antenna apparatus and associated methods. In one embodiment, a switching antenna configuration is used within a portable device (e.g. mobile phone). The switching antenna comprises at least one antenna element which operates at one or more resonant frequencies, and one or more switching elements. In one implementation, the switching elements are autonomously controlled to correct for detuning effects experienced by the antenna (e.g., body tissue loading) by modifying the electrical length of the antenna radiator(s) and/or correcting antenna impedance mismatch. In another implementation, the switching elements are controlled to effectuate band switching of the antenna.

Abstract: A method and an arrangement for matching the antenna of a radio device in transmitting condition. The antenna impedance in the output of the power amplifier of a transmitter is adjusted by means of a ?-shaped reactive matching circuit, the component values of which can be selected from a relatively wide array of the alternatives. The component values are selected using multiple-way switches, which only are located in the transverse branches of the matching circuit. The switches are set by the control unit, input variables of which being the SWR value provided by the directional coupler, the operating band used each time and a value of the transmitting power. The matching is based on an adjusting process to be executed at regular intervals, in which process the control unit tries different combinations of the switch states and finally selects the combination, which brings the lowest SWR value.

Abstract: A space efficient multi-feed antenna apparatus, and methods for use in a radio frequency communications device. In one embodiment, the antenna assembly comprises three (3) separate radiator structures disposed on a common antenna carrier. Each of the three antenna radiators is connected to separate feed ports of a radio frequency front end. In one variant, the first and the third radiators comprise quarter-wavelength planar inverted-L antennas (PILA), while the second radiator comprises a half-wavelength grounded loop-type antenna disposed in between the first and the third radiators. The PILA radiators are characterized by radiation patterns having maximum radiation axes that are substantially perpendicular to the antenna plane. The loop radiator is characterized by radiation pattern having axis of maximum radiation that is parallel to the antenna plane.

Abstract: Apparatus and methods for matching the antenna of a radio device. In one embodiment, a capacitive sensor is arranged in the antenna structure and configured to detect the electric changes in the surroundings of the antenna. The mismatch caused by a change is rectified by means of the signal proportional to the sensor capacitance. This capacitance and the frequency range currently in use are input variables of a control unit. The antenna impedance is adjusted by means of a reactive matching circuit, the component values of which can be selected from a relatively wide array of alternatives by way of change-over switches, which are located in the transverse branches of the matching circuit.

Abstract: A chassis-excited antenna apparatus, and methods of tuning and utilizing the same. In one embodiment, a distributed loop antenna configuration is used within a handheld mobile device (e.g., cellular telephone). The antenna comprises two radiating elements: one configured to operate in a high-frequency band, and the other in a low-frequency band. The two antenna elements are disposed on different side surfaces of the metal chassis of the portable device; e.g., on the opposing sides of the device enclosure. Each antenna component comprises a radiator and an insulating cover. The radiator is coupled to a device feed via a feed conductor and a ground point. A portion of the feed conductor is disposed with the radiator to facilitate forming of the coupled loop resonator structure.

Abstract: A method and an arrangement for matching the antenna of a radio device in transmitting condition. The antenna impedance in the output of the power amplifier of a transmitter is adjusted by means of a ?-shaped reactive matching circuit, the component values of which can be selected from a relatively wide array of the alternatives. The component values are selected by means of the multiple-way switches, which only are located in the transverse branches of the matching circuit. The switches are set (706) by the control unit, input variables of which being the SWR value provided by the directional coupler, the operating band used each time and a value of the transmitting power. The matching is based on an adjusting process to be executed at regular intervals, in which process the control unit tries different combinations of the switch states and finally selects (710) the combination, which brings the lowest SWR value.