Abstract: A wireless communication device and method includes an auxiliary antenna that can actively cancel at least a portion of a near-field component of an electric field generated by a main transmit antenna. The auxiliary antenna can help comply with specific absorption rate requirements and can reduce undesirable signal rectification in hearing aid components.

Abstract: A system for production of an electromagnetic (EM) field having EM emissions mitigated at one or more predetermined locations within a Hearing Aid Compliant (HAC) measurement plane is provided. The EM field mitigation system includes a ground plane, an antenna element, and a parasitic resonator element. The antenna element is coupled to the ground plane and resonates within at least one predetermined frequency band for transmitting and receiving the radio frequency (RF) signals modulated at one or more frequencies within the at least one predetermined first frequency band.

Abstract: A system for production of an electromagnetic (EM) field having EM emissions mitigated at one or more predetermined locations within a Hearing Aid Compliant (HAC) measurement plane is provided. The EM field mitigation system includes a ground plane, an antenna element, and a parasitic resonator element. The antenna element is coupled to the ground plane and resonates within at least one predetermined frequency band for transmitting and receiving the radio frequency (RF) signals modulated at one or more frequencies within the at least one predetermined first frequency band.

Abstract: A system for production of an electromagnetic (EM) field having EM emissions mitigated at one or more predetermined locations within a Hearing Aid Compliant (HAC) measurement plane is provided. The EM field mitigation system includes a ground plane, an antenna element, and a parasitic resonator element. The antenna element is coupled to the ground plane and resonates within at least one predetermined frequency band for transmitting and receiving the radio frequency (RF) signals modulated at one or more frequencies within the at least one predetermined first frequency band. The parasitic resonator element includes at least a first leg and a second leg connected to the ground plane and located a predetermined distance from the antenna element for mitigation of the EM emissions of the antenna element at the one or more predetermined locations within the HAC measurement plane.

Abstract: A method (1400) and an RF circuit (100, 400, 700, 1000, 1100, 1200, 1300) for a wireless communication device that mitigates near field radiation generated by the wireless communication device. At least one counterpoise (104, 404, 1304) can be configured to resonate at or near at least one operating frequency of an antenna (102) of the wireless communication device. The antenna can be a component of the RF circuit. The counterpoise can be electromagnetically coupled to the antenna to mitigate near field radiation of the antenna at the at least one operating frequency of the antenna in order to comply with an applicable hearing aid compatibility (HAC) specification.

Abstract: A system for production of an electromagnetic (EM) field having EM emissions mitigated at one or more predetermined locations within a Hearing Aid Compliant (HAC) measurement plane is provided. The EM field mitigation system includes a ground plane, an antenna element, and a parasitic resonator element. The antenna element is coupled to the ground plane and resonates within at least one predetermined frequency band for transmitting and receiving the radio frequency (RF) signals modulated at one or more frequencies within the at least one predetermined first frequency band. The parasitic resonator element includes at least a first leg and a second leg connected to the ground plane and located a predetermined distance from the antenna element for mitigation of the EM emissions of the antenna element at the one or more predetermined locations within the HAC measurement plane.

Abstract: A wireless communication device and method includes an auxiliary antenna that can actively cancel at least a portion of a near-field component of an electric field generated by a main transmit antenna. The auxiliary antenna can help comply with specific absorption rate requirements and can reduce undesirable signal rectification in hearing aid components.

Abstract: A method (1400) and an RF circuit (100, 400, 700, 1000, 1100, 1200, 1300) for a wireless communication device that mitigates near field radiation generated by the wireless communication device. At least one counterpoise (104, 404, 1304) can be configured to resonate at or near at least one operating frequency of an antenna (102) of the wireless communication device. The antenna can be a component of the RF circuit. The counterpoise can be electromagnetically coupled to the antenna to mitigate near field radiation of the antenna at the at least one operating frequency of the antenna in order to comply with an applicable hearing aid compatibility (HAC) specification.

Abstract: A dual-band cellular telephone antenna. A monopole antenna is tuned to a first resonant frequency of operation. A first helical antenna is coupled to the monopole antenna and has turns surrounding the monopole antenna, where the first helical antenna is tuned to a second resonant frequency of operation. A grounded second helical antenna surrounds the first helical antenna and is formed to have an upper capacitive loading segment to tune the grounded second helical antenna at substantially the second resonant frequency of operation. The cellular telephone has a housing formed of a conductive material. A printed circuit board (PCB) has a metalized ground plane, wherein the metalized ground plane and the grounded second helical antenna are coupled to the cellular telephone housing.

Abstract: An antenna assembly for a mobile communication device. The antenna assembly can include a RF connection feed point and a planar radiating element including a conductive area split by a nonconductive gap which divides the planar radiating element into a first arm having an end coupled to the RF connection feed point and a second arm having an end coupled to the RF connection feed point. The antenna assembly can also include a first connection point coupled to the opposite end of the first arm from the RF connection feed point, the first connection point being selectively coupled to an impedance.

Abstract: An antenna assembly for a mobile communication device. The antenna assembly can include a RF connection feed point and a planar radiating element including a conductive area split by a nonconductive gap which divides the planar radiating element into a first arm having an end coupled to the RF connection feed point and a second arm having an end coupled to the RF connection feed point. The antenna assembly can also include a first connection point coupled to the opposite end of the first arm from the RF connection feed point, the first connection point being selectively coupled to an impedance.

Abstract: A multi-band radio communication device with an antenna system that includes an antenna element and a parasitic element located in proximity to the antenna element. A tuning circuit is coupled to the parasitic element. The tuning circuit is variable to adjust the parasitic load on the antenna element to provide variable operating frequencies and bandwidths for the communication device.

Abstract: A communication device operable in multiple frequency bands includes a branching antenna adapted to operate in at least two frequency bands. The antenna includes a first conductive element having a connection at one end for driving the antenna. The first conductive element is resonant at a first frequency. On the first conductive element, a feed point is located away from either end of the first conductive element, and particularly the driving connection point. A second conductive element is coupled to the feed point such that the second conductive element in conjunction with the portion of the first conductive element between the drive connection and the feed point is resonant at a second frequency. This allows for a more compact and versatile multi-band antenna.

Abstract: An improved antenna system to channel counterpoise currents for an unbalanced antenna such as a helical monopole. A first conductor, or ground resonator, is coupled to a ground connection near the antenna and is located distally from a user to reduce electromagnetic exposure. The first conductor presents a low impedance path at an operating frequency of the antenna such that RF currents are attracted onto the first conductor. A second conductor, such as a printed circuit board or user interface circuitry, is also coupled to the ground connection of the first conductor. The second conductor presents a high impedance path at the operating frequency of the antenna such that RF currents are diverted away from the second conductor which is held closer to a user than the first conductor.