Abstract:
1. 청구범위에 기재된 발명이 속한 기술분야 소형 루프안테나에 관한 것임. 2. 발명이 해결하고자 하는 기술적 과제 다수의 공진주파수를 발생시키고, 안테나 효율이 높은 소형 루프안테나를 제공함. 3. 발명의 해결방법의 요지 동축케이블로 구현되는 제1안테나소자 상기 제1안테나소자와 직렬 연결되며 도선으로 구현되는 제2안테나소자 상기 제1안테나소자와 직렬 연결되되, 제1안테나소자와 제2안테나소자가 연결된 단부의 타단에 직렬 연결되고 도선으로 구현되며 일단이 접지되는 제3안테나소자 및 상기 제2안테나소자로 전원을 공급하는 급전케이블을 포함하는 안테나를 제공함. 4. 발명의 중요한 용도 소형안테나에서 이용됨. 루프 안테나, 케이블 루프 안테나, 다중 급전
Abstract:
A system and method for receiving an antenna measuring signal and system for the same is provided to minimize a measuring error of the antenna by removing a coupling effect of an RF cable at the antenna. An RX-antenna module(108) receives an antenna measurement signal of the radio frequency signal. An electrical-optical conversion module(110) converts the antenna measurement signal received in the RX-antenna module into the optical signal. An optical-electrical conversion module(112) converts the antenna measurement signal from the electric-optic conversion module into the electric signal. An optical cable(111) connects the output port of the electric-optic conversion module into an optical-electrical conversion module. The electric-optic conversion module comprises the impedance matching module for performing the impedance matching between the input port of the output port of the RX-antenna module and the electric-optic conversion module.
Abstract:
본 발명은 배열 안테나를 구성하는 소자안테나 혹은 부배열 안테나의 개별적인 동작을 전기적 또는 기계적으로 제어할 수 있고, 그에 따라 통신환경 변화에 능동적으로 대처할 수 있으며, 경제적이면서도 고성능의 송수신 기능을 갖는 기지국 및 중계기 안테나 및 그 안테나의 모드 제어방법을 제공한다. 그 안테나는 1개 이상의 배열 안테나를 구비하고, 안테나 유효 개구면의 선택적 가변 및 안테나 빔 패턴의 지향 방향을 변경할 수 있는 방사부; 상기 배열 안테나에 연결되며, 스위치, 송신 및 수신 채널, 및 신호 결합 및 분배기를 구비한 능동 채널부; 및 상기 능동 채널부에 연결되며 제어부 및 모뎀을 구비한 모뎀 및 제어부;를 포함하고, 통신환경에 따라 기지국 및 중계장비의 서비스 영역을 능동적으로 가변할 수 있다. 안테나, 다중 모드 안테나, 기지국 안테나
Abstract:
A method and an apparatus for CQI(Channel Quality Indicator) control for adaptive modulation and coding in an OFDMA system improve capacity and fairness of the OFDMA system by variably controlling a size of a sub carrier group. A valid cluster is selected among clusters including one bin or more which are a plurality of subcarrier groups according to a predetermined standard(S335). An average CINR(Carrier-to-Interference-plus-Noise Ratio) of the valid cluster is calculated(S337). The optimum MCS level of each valid cluster is determined based on the average CINR value(S353). The optimum cluster among the valid clusters is determined based on the optimum MCS level(S373).
Abstract:
A probe is provided to improve accuracy in measuring a near field of an antenna by reducing multi-reflection through a first waveguide while maintaining a cut-off frequency impinged to the probe. A probe includes a first waveguide(10), a second waveguide(20), and a third waveguide(30). The first waveguide includes a first opening surface and a second opening surface. The first opening surface receives an electromagnetic wave and the second opening surface has the same width and height as the first opening surface. The second waveguide includes a third opening surface and a fourth opening surface. The third opening surface has the same width and height as the second opening surface. The fourth opening surface has the same width as the third opening surface and a larger height than the third opening surface. The third opening surface is in contact with the second opening surface. The third waveguide includes a fifth opening surface and a sixth opening surface. The fifth opening surface has the same width and height as the fourth opening surface. The sixth opening surface has smaller width and height than the fifth opening surface. The fifth opening surface is in contact with the fourth opening surface.
Abstract:
A UWB(Ultra Wide Band) transceiver for frequency sharing and a transceiving method are provided to reduce interference effect of an external device by selectively controlling transmission power, thereby making frequency sharing with the external device available. An external signal detector(120) detects an external signal generated from an external system. If an external signal using the same frequency channel as a UWB transceiver is detected, a transmission signal controller(130) determines size of a transmission signal of the UWB transceiver according to size of the detected external signal. If the external signal is not detected, a maximum power generator(160) generates a maximum power level of the transmission signal.
Abstract:
A comb polarizer suitable for millimeter band applications is provided to simplify a structure and reduce cost by inserting only a comb conductive plate between conventional circular waveguides. A comb polarizer suitable for millimeter band applications includes a waveguide and a comb conductive unit. The waveguide has an arbitrary opening surface which consists of two separable half waveguides(11). The comb conductive unit has a shape of a comb with a plurality of cogs which are inserted between the two half waveguides(11) to convert an incident linear polarization signal to a circular polarization signal.
Abstract:
A method for sensing spectrum and arranging quiet period in a cognitive radio system, a CPE(Customer Premise Equipment), a base station and a superframe structure using the same are provided to increase the reliability of detection regarding whether an incumbent user appears in his/her frequency channel. A base station(800) using a method for sensing spectrum and arranging quiet period in a cognitive radio system comprises a transceiver(802) and a sensor(804). The base station(800) constructs a WRAN(Wireless Regional Area Network) with the first CPE(810) and the second CPE(820). The first CPE(810) includes a transceiver(812) and a sensor(814). The second CPE(820) includes a transceiver(822) and a sensor(824). The transceiver(802) communicates with the first CPE(810) via the first frequency channel CH_1, communicates with the second CPE(820) via the second frequency channel CH_2, and does not perform transmission via the first or the second frequency channel CH_1 or CH_2 during a QP of the base station(800). The transceiver(802) may transmit information on the assignment of QPs of the first and second frequency channels CH_1 and CH_2 belonging to an active set to the first CPE(810) and the second CPE(820). The transceiver(802) may receive each result obtained by performing spectrum sensing for the first CPE(810) and the second CPE(820) from the first CPE(810) and the second CPE(820). Therefore, the base station(800) can utilize a result obtained by performing spectrum sensing and the results obtained by performing spectrum sensing for the first CPE(810) and the second CPE(820), thereby performing more reliable spectrum sensing. The sensor(804) performs spectrum sensing for the first frequency channel CH_1 during a QP of the first frequency channel CH_1, converts the first frequency channel CH_1 into the second frequency channel CH_2 before a QP of the second frequency channel CH_2, and performs spectrum sensing for the second frequency channel CH_2 during a QP of the second frequency channel CH_2.
Abstract:
A satellite tracking antenna system is provided to improve accuracy of satellite tracking by mounting a satellite tracking receiver having a tracking signal processing function in a digital mode on the antenna system. A transmitting/receiving unit has a transmitting channel and a receiving channel for signal power. A driving unit performs mechanical motion of the rotating body for satellite tracking. A control unit monitors and controls the operation of the driving unit. The transmitting channel includes a rotary joint(110) providing a channel between a rotating body and a fixed body, a transceiver common unit(109) controlling on and off through a built-in RF switch, a block up converter(105) for frequency up-converting an inputted baseband signal into an RF band signal, and a power amplifier(104) amplifying the RF signal from the block up converter to a high output.
Abstract:
본 발명은 직교 주파수 분할 다중 접속(Orthogonal Frequency Division Multiplexing Access : OFDMA) 기반 인지 무선 시스템에서의 동적 자원 할당 방법 및 이를 위한 하향 링크 프레임 구조에 관한 것으로, 이 방법은 기지국이, 현재 사용되지 않는 유휴주파수대역의 주파수 선택성 정도에 따라, 적어도 하나의 빈-상기 빈은 주파수 상에서 연속된 제1 복수 개의 부반송파들로 이루어짐-으로 이루어진 부채널을 할당하는 AMC부채널 할당기법 및 주파수 상에서 분산형 제2 복수 개의 부반송파들로 이루어진 부채널을 할당하는 다이버시티부채널 할당기법 중 하나를 선택하는 선택단계; 및 상기 기지국이, 상기 선택된 부채널 할당기법에 따라 단말에게 적어도 하나의 부채널을 할당하는 할당단계를 포함한다. 본 발명에 따르면, 인지 무선 시스템에서 하향 링크의 효율을 높일 수 있다. OFDMA/FDD, 프레임 구조, 부채널