The present invention is directed at an electromagnetic field monitoring device configured to continuously monitor properties of an electromagnetic field. The device may be solely powered by the ambient electromagnetic energy of an electromagnetic field, removing any reliance on external power sources or batteries. Monitored properties may include real-time electromagnetic field strength, peak electromagnetic field strength in a time period, electromagnetic field exceedance, and cumulative electromagnetic field dose. The device detects otherwise concealed sources of electromagnetic fields, such as hidden cameras or microphones. The device may be integrated into a variety of products, including, but not limited to, a keychain attachment, lanyard attachment, eyeglasses frame, handheld instrument, identification card, writing instrument, business card, adhesive sticker, ring, or necklace pendant.

The present invention is directed at an electromagnetic field monitoring device configured to continuously monitor properties of an electromagnetic field. The device may be solely powered by the ambient electromagnetic energy of an electromagnetic field, removing any reliance on external power sources or batteries. Monitored properties may include real-time electromagnetic field strength, peak electromagnetic field strength in a time period, electromagnetic field exceedance, and cumulative electromagnetic field dose. The device detects otherwise concealed sources of electromagnetic fields, such as hidden cameras or microphones. The device may be integrated into a variety of products, including, but not limited to, a keychain attachment, lanyard attachment, eyeglasses frame, handheld instrument, identification card, writing instrument, business card, adhesive sticker, ring, or necklace pendant.

Single band and multiband wireless antennas are an important element of wireless systems. Competing tradeoffs of overall footprint, performance aspects such as impedance matching and cost require not only consideration but become significant when multiple antenna elements are employed within a single antenna such as to obtain circular polarization transmit and/or receive. Accordingly, it would be beneficial to provide designers of a wide range of electrical devices and systems with compact single or multiple frequency band antennas which, in addition to providing the controlled radiation pattern and circular polarization purity (where required) are impedance matched without substantially increasing the footprint of the antenna and/or the complexity of the microwave/RF circuit interfaced to them, whilst supporting multiple signals to/from multiple antenna elements in antennas employing them. Solutions present achieve this through provisioning one or more capacitive series reactances discretely or in combination with one or more shunt capacitive reactances.

An antenna includes a first radiator, a second radiator, and a feed. The first radiator has a first feed point and a first ground point. The second radiator has a second feed point and a second ground point. The antenna further includes a connection line. The connection line has a first end and a second end that are opposite to each other. The first end is coupled to the first feed point of the first radiator, and the second end is coupled to the second feed point of the second radiator. A feeding point is disposed on the connection line, and the feeding point is coupled to the feed.

An antenna device includes a ground electrode, a feed element, and a parasitic element. The ground electrode has a substantially non-square rectangular plane shape that includes a first side extending in a first direction and a second side extending in a second direction orthogonal to the first direction. The feed element has a substantially rectangular plane shape and is formed in such a way that each side of the feed element becomes parallel to the first direction or the second direction. The parasitic element is formed in such a manner as to face a side of the feed element parallel to the first side. The feed element is configured to radiate a first polarized wave that excites in the first direction and a second polarized wave that excites in the second direction. The length of the first side is longer than the length of the second side.

Provided is an antenna device with a simple configuration, said antenna device supporting a plurality of frequency bands. An antenna device according to the present invention is provided with: at least one first radiation element that has a resonant frequency in a first frequency band; at least one second radiation element; and a connection line for connecting the first radiation element and the second radiation element. The line length formed of the first radiation element, the connection line, and the second radiation element is set to a length so as to have a resonant frequency in a second frequency band lower than the first frequency band.

Provided is an antenna device with a simple configuration, said antenna device supporting a plurality of frequency bands. An antenna device according to the present invention is provided with: at least one first radiation element that has a resonant frequency in a first frequency band; at least one second radiation element; and a connection line for connecting the first radiation element and the second radiation element. The line length formed of the first radiation element, the connection line, and the second radiation element is set to a length so as to have a resonant frequency in a second frequency band lower than the first frequency band.

An antenna for a mobile device includes a ground element, a substrate disposed over the ground element, a first radiating element having a feedpoint, a second radiating element coupled to the ground element and adjacent the first radiating element, and a connection metal element disposed on the substrate, and a coaxial cable, having central conductor coupled to the feedpoint, a shielding conductor, and an insulating outer layer, wherein the shielding conductor has a bare region, spaced from the feedpoint, that exposes a portion of the shielding conductor, and the portion of the shielding conductor is coupled through the connection metal element to the second radiating element.

An electronic device and an antenna structure are provided. The electronic device includes a metal housing, a partition wall, a first antenna module, and a second antenna module. The metal housing has a T-shaped slot. The slot includes an opening end, a first closed end, and a second closed end. The partition wall is connected with the metal housing. The first antenna module has a first feeding element and a radiating element. The second antenna module has a second feeding element and an antenna array. The first antenna module and the second antenna module are respectively disposed on two sides of the partition wall, and the first antenna module is closer to the opening end than the second antenna module.

An electronic device and an antenna structure are provided. The electronic device includes a metal housing, a partition wall, a first antenna module, and a second antenna module. The metal housing has a T-shaped slot. The slot includes an opening end, a first closed end, and a second closed end. The partition wall is connected with the metal housing. The first antenna module has a first feeding element and a radiating element. The second antenna module has a second feeding element and an antenna array. The first antenna module and the second antenna module are respectively disposed on two sides of the partition wall, and the first antenna module is closer to the opening end than the second antenna module.