Disclosed is a wide-band conformal coaxial antenna conformal to a surface that comprises an inner conductor, an outer conductor, and a dielectric layer. The inner conductor extends towards the surface from a coaxial input below the surface and the outer conductor surrounds the inner conductor extending from the coaxial input to the surface. The dielectric layer is between the inner conductor and the outer conductor. The inner conductor has a first inner conductor diameter at the coaxial input and a second inner conductor diameter at a distal end of the inner conductor at or proximately below the surface. The inner conductor forms an inner conductor surface at the distal end of the inner conductor and the second inner conductor diameter is larger than the first inner conductor diameter. The outer conductor has a first outer conductor diameter at the coaxial input and a second outer conductor diameter at the surface. The second outer conductor diameter is larger than the first outer conductor diameter.

A communication system provides wireless communication in locations of restricted movement. Restricted movement may include static locations (for example, buildings and tunnels) or moving vehicles (for example, elevators, trains, and ships). A wireless antenna may be connected to an external telecommunications source through a radiant cable. Wireless signals may thus provide communication from locations that were previously subject to spotty or unreachable signal. Direct communication from occupants may be provided. Some embodiments may provide monitoring or equipment or the environment that previously required a hardwired line.

A method for controlling gain of a line amplifier on a cable, the method comprising selecting an unused carrier frequency; transmitting a pulsed pilot signal on the unused carrier frequency into the cable; determining a pilot signal output strength by measuring signal strength of the pilot signal after amplification by the line amplifier; comparing the pilot signal output strength with a target signal strength to determine a difference; and adjusting the gain of the line amplifier corresponding to the difference.

A wireless communication system including a shield room forming section, leaky transmission line, first antenna, first device, second antenna and second device. The shield room forming section covers an internal space with an electromagnetic wave reflector that blocks wireless communication. The leaky transmission line is provided with first and second leakage parts arranged inside the shield room forming section. The first antenna is arranged inside the shield room forming section and configured to be wirelessly communicable with the first leakage part. The first device is arranged inside the shield room forming section and has the first antenna. The second antenna is arranged inside the shield room forming section and configured to be wirelessly communicable with the second leakage part. The second device is arranged inside the shield room forming section and has the second antenna. The first device and the second device perform direct two-way wireless communication with each-other.

Disclosed is a communication system for positioning of a terminal device. The communication system includes at least three leaky coaxial cables, a server device for determining a position of a terminal device in response to a receipt of data from the terminal device through at least two coaxial cables. The server device is arranged to determine an indicator value representing the at least two coaxial cables through which the data from the terminal device is received and to compare the indicator value to change patterns stored in data storage accessible to the server device, and in response to a match in a comparison to generate data representing the position of the terminal device. Also disclosed is a method for positioning the terminal device.

An in-cabin communication system performs wireless communication between a vehicle and a portable terminal carried by an occupant. The in-cabin communication system includes: a vehicular device mounted to the vehicle; and a leaky coaxial cable that is connected to the vehicular device, and that outputs an electromagnetic wave having a predetermined wavelength according to a command from the vehicular device. The leaky coaxial cable is disposed inside a steel plate of a body of the vehicle. The leaky coaxial cable is disposed at a predetermined distance, which corresponds to an integer multiple of a half-wavelength of the predetermined wavelength, from the steel plate.

A system for EMNZ metamaterial-based direct antenna modulation. The system includes a signal generator, a metamaterial switch and an antenna. The signal generator may is configured to generate a microwave signal. The metamaterial switch is configured to generate a modulated microwave signal from the microwave signal. The modulated microwave signal is generated by selectively passing the microwave signal through the metamaterial switch. The metamaterial switch includes a first conductive plate and a first loaded conductive plate. The first loaded conductive plate includes a second conductive plate and a first monolayer graphene. The first monolayer graphene includes a first tunable conductivity. The first monolayer graphene is positioned between the first conductive plate and the second conductive plate. An effective permittivity of the metamaterial switch is configured to be adjusted to a predetermined value. The effective permittivity of the metamaterial switch is adjusted responsive to tuning the first tunable conductivity.

In a method for reading from an RFID-tagged article and an RFID system, information is accurately read from an RFID tag while interference with other devices is prevented by use of a compact and simple configuration. An article is conveyed on a conveyor belt. Also, an RFID tag is attached to the article. Information on the RFID tag is read by a leaky coaxial cable that is a stationary read/write antenna in a vicinity of the conveyor belt. The leaky coaxial cable is above the conveyor belt and at least a portion of the cable traverses the conveyor belt.

A cable antenna an end part of which is connected to an oscillator that supplies a high-frequency current is disclosed. The cable antenna includes: an inner conductor; an insulating layer covering the inner conductor; and an outer conductor covering the insulating layer, wherein only one exposed part is formed in a middle part of the cable antenna in a longitudinal direction, the exposed part formed by removing at least the outer conductor, a distance L between a tip end of the cable antenna and an end of the exposed part on a side closer to the tip end is an odd multiple of a quarter of a wavelength , of the high-frequency current, the multiplier being three or greater, and a length G of the exposed part in the longitudinal direction satisfies the following formula (1):
/20G</4(1) : wavelength (mm) of the high-frequency current.

A wireless proximity detection system employs short-range wireless communication to detect the proximity of a user device within a strictly defined wireless zone and as a result trigger a desired action. The proximity detection system may utilize one or more leaky feeders to define the wireless zone and the associated received signal strength(s) detected by the user's wireless device. Alternatively, a compact planar antenna structure coupled with a highly shielded radio transceiver is used to allow a similar precise low-power radio beam to be emitted defining a small location to enable identification of a wireless device such as a smartphone in a given area in front of the device. The planar antenna structure allows a compact and low-cost fabrication method and the use of common printed circuit fabrication methods provide an integrated solution.