Showing papers on "Active antenna published in 2011"

Low cost, active antenna arrays

Abstract: A transmitter system including: a bidirectional signaling (BDS) network having first and second networks for carrying first and second carrier signals, and having a set of n phase synchronous location pairs (a i , b i ),; and also including tunable transmitter circuits for driving an antenna array, each tunable transmitter circuit having an output line for carrying an output signal and first and second input lines electrically connected to the first and second networks of the BDS network at locations of a corresponding one of the set of phase synchronous location pairs, and including a multiplier having a first input electrically connected to the first input line of that tunable transmitter circuit; a phase setting circuit electrically connected to the multiplier for controlling the phase of the output signal of that tunable transmitter circuit; and an amplitude setting circuit for controlling the amplitude of the output signal of that tunable transmitter circuit.

A Lightweight Organic X-Band Active Receiving Phased Array With Integrated SiGe Amplifiers and Phase Shifters

Abstract: This paper presents for the first time an X-band antenna array with integrated silicon germanium low noise amplifiers (LNA) and 3-bit phase shifters (PS). LNAs and PSs were successfully integrated onto an 8 × 2 lightweight antenna utilizing a multilayer liquid crystal polymer (LCP) feed substrate laminated with a duroid antenna layer. A baseline passive 8×2 antenna is measured along with a SiGe integrated 8×2 receive antenna for comparison of results. The active antenna array weighs only 3.5 ounces and consumes 53 mW of dc power. Successful comparisons of the measured and simulated results verify a working phased array with a return loss better than 10 dB across the frequency band of 9.25 GHz-9.75 GHz. A comparison of radiation patterns for the 8×2 baseline antenna and the 8×2 SiGe integrated antenna show a 25 dB increase in gain (ΔG). The SiGe integrated antenna demonstrated a predictable beam steering capability of ±41°. Combined antenna and receiver performance yielded a merit G/T of -9.1 dB/K and noise figure of 5.6 dB.

A wideband metamaterial-inspired compact antenna using embedded non-Foster matching

Abstract: Passive electrically small antennas have a small radiation resistance and a narrow bandwidth. In this paper, a new type of active antenna is reported in which an active circuit generating a non-Foster impedance is embedded in a metamaterial-inspired small antenna with an inherent sizable radiation resistance. This circuit interacts with the reactive elements of the antenna. The end result is a compact, broadband antenna which is well matched and has the potential for a high efficiency. In this process, the need for an active (or passive) step-up transformer for the radiation resistance is eliminated. This work opens up the possibility of utilizing non-Foster components embedded in metamaterial-based antenna structures to obtain efficient antennas by manipulating the current and field distribution in and around the antenna.

Miniaturized Self-Oscillating Annular Ring Active Integrated Antennas

Abstract: With a direct integration of a field effect transistor (FET) into a C-shaped ring radiator, a novel miniaturized self-oscillating annular ring active integrated antenna is proposed and investigated in this paper. The direct integration approach provides a solid basis for the miniaturization while the slow-wave loading effect from the unstable transistor further enhances the reduction ratio. It makes the proposed design show an extraordinarily compact size of 0.041λg2 , which is 40% the size of the second smallest one in literature using printed circuit board technology. The proposed active antenna, providing overall comparable performance to the previous designs, has an EIRP of 7.30 dBm, DC-to-RF efficiency of 25.9%, phase noise of -91.9 dBc/Hz@100 kHz offset, and an oscillator FOM of -168.76 dBc/Hz. By introducing a reverse-biased varactor diode, this miniaturized active antenna also demonstrates promising voltage controllability with a high VCO gain of 48.7 MHz/V. The antenna geometry and modeling, design concept, simulation scheme, and experimental results are discussed thoroughly in this paper.

Antenna array and method for operating antenna array

Abstract: The present invention refers to an active antenna array having a plurality of antenna elements comprising: at least one first subset of the plurality of antenna elements, the at least one first subset relaying a first radio signal having a first antenna beam pattern; and at least one second subset of the plurality of antenna elements, the at least one second subset relaying a second radio signal having a second antenna beam pattern, wherein at least one of the plurality of antenna elements is a common antenna element belonging to both the first subset and the second subset. A method for operating the active antenna array is also disclosed.

Antenna system coupled to an external device

Abstract: An antenna system is integrated into a cover or accessory and adapted to couple to an antenna in a host device to improve transmission and reception of signals. The antenna system can be passive or active, with the active antenna system designed to amplify coupled signals on the integrated antenna elements in the cover or accessory. Single or multiple frequency bands can be improved with the integrated antenna system, and multiple antennas in the host device can be coupled to and improved. The antenna system can couple to the existing antennas in the host device by capacitive coupling, i.e. no physical contact required, or a connector can be designed into the cover or accessory containing the integrated antenna system that makes contact to electrical ground of the host device or power supply signals or other control signals.

Calibration of active antenna arrays for mobile telecommunications

Abstract: In order to calibrate in amplitude and phase the individual transceiver elements (4) of an active antenna array for a mobile telecommunications network, each transceiver element including a transmit and a receive path (8, 10) coupled to an antenna element (12), each transceiver element includes a comparator (100) for comparing phase and amplitude of transmitted or received signals with reference signals in order to adjust the characteristics of the antenna beam. In order to provide an accurate means of reference signal distribution, a feed arrangement distributes the reference signals and includes a waveguide (50) of a predetermined length which is terminated at one end (52) in order to set up a standing wave system along its length, and a plurality of coupling points (56) at predetermined points along the length of the waveguide, which are each coupled to a comparator of a respective transceiver element.

EM/Circuit Mixed Simulation Technique for an Active Antenna

Abstract: Today's increase of functions, improvement of performance, and cost reductions required on an active electronically scanned array (AESA), associated to the limited amount of available areas and volumes to implement the equipment, drive an approach leading to directly connect power amplifiers (PAs) to the antennas array without placing an isolator/circulator between them. In this letter, an electromagnetic/radio frequency (EM/RF) circuit mixed simulation technique will be theoretically introduced and experimentally demonstrated on transmission (Tx) chains to deal with the proposed challenge.

Low cost 60 GHz RF front end transceiver integrated on organic substrate

Abstract: This paper presents, for the first time, a low cost, 60 GHz, RF front-end Tx/Rx integrated with a Yagi-Uda antenna array on organic Liquid Crystal Polymer substrate. The Tx/Rx module consists of a GaAs LNA, PA and a Single Pole Double Throw (SPDT) switch wirebonded on a single, multilayer substrate. The array was designed for operation at 60.6 GHz with a gain of 12.1 dBi. The radiation pattern measurements were conducted and showed an active antenna gain of 31.8 dB for the receiver and 21.6 dB of gain for the transmitter. It demonstrates 19.7 dB and 9.5 dB of added gain from the integrated receive and transmit modules respectively. The array has 1 and 3 dB deviation in gain in receiver and transmitter modules respectively from 55–63 GHz.

Modular millimeter-wave radio frequency system

Abstract: A modular millimeter-wave radio frequency (RF) system comprises a plurality of active antenna arrays for receiving and transmitting millimeter-wave RF signals; and a plurality of RF sub-modules for performing at least up and down conversions of intermediate frequency (IF) signals and controlling the plurality of antenna arrays, each of the plurality of RF sub-modules is connected to an antenna array of the plurality of antenna arrays, wherein the plurality of RF sub-modules are chained to each other through a first transmission line and one of the plurality of RF sub-modules is connected to a baseband module through a second transmission line, each of the first transmission line and the second transmission line transfers a multiplexed signal including an IF signal, a local oscillator (LO) signal, a control signal, and a power signal

Active antenna array and method for relaying radio signals

Abstract: The present disclosure teaches an active antenna array for a mobile communications network. The active antenna array comprises a base band unit, a plurality of transceiver units terminated by at least one antenna element; and at least one link, The link couples the individual ones of the plurality of transceiver units to the base band unit. The link is a digital link and is adapted to relay a payload signal at a selectable pay load rate. The digital link is further adapted to relay a timing signal at a fixed timing rate, when the timing signal is embedded in the payload at a selectable payload rate. The present disclosure further teaches a method for relaying radio signals and a computer program for manufacturing the active antenna array and for executing me method.

Travelling wave distributed active antenna radiator structures, high frequency power generation and quasi-optical filtering

Abstract: An integrated distributed active radiator (DAR) device includes first and second conductors disposed adjacent to each other. The conductors define curves which close on themselves to within a distance of a gap. The first conductor first end is electrically coupled to the second conductor second end across the gap. The second conductor first end is electrically coupled to the first conductor second end across the gap. At least one active element is configured to produce a self-oscillation current at a frequency fo. The self-oscillation current has a first direction in the first conductor and a second direction in the second conductor. The DAR device is configured to generate a harmonic current having a harmonic frequency which has the same direction in both conductors. The DAR device is configured to efficiently radiate electromagnetic energy at the harmonic frequency and to substantially inhibit the radiation of electromagnetic energy at the frequency fo.

Test method for uplink and downlink directional diagrams and gain of active antenna

Abstract: The invention provides a test method for the performance parameter of an active antenna. According to the characteristic that an uplink and a downlink of the active antenna can not be reciprocal, in the invention, different platforms are designed for respectively testing the uplink and the downlink so as to accurately measure the uplink and the downlink antenna directional diagrams and the gain of the active antenna. The test method for the uplink and the downlink directional diagrams and the gain of the active antenna is a novel test method, which is provided for the active antenna and developed on the basis of a traditional passive antenna. Because no effective measuring method is designed for the uplink and the downlink directional diagrams and the gain of the active antenna at present, the method in the invention can be used for accurately measuring the uplink and the downlink directional diagrams and the gain of various active antennas through the matched design of related parts at the far end, the inner part and the near end of a microwave darkroom and the real-time record control of a control computer, thereby favorably promoting the development of the active antenna.

60-GHz switched-beam end-fire antenna module integrated with novel microstrip-to-slot transition

Abstract: Summary form only given, as follows. A low profile, switched-beam, end-fire antenna integrated with a novel microstrip-to-slot transition is presented. The antenna module consists of wire-bonded switch and PA integrated in liquid crystal polymer substrate package. The proposed transition exploits slow-wave techniques to transform a 50O microstrip into a 110O slot mode over 55 to 67+ GHz. The 10mm × 10mm active antenna 3dB beamwidth is 55°/68° (E/H plane) in each switched state with an average 19 dBi peak gain over 55 to 67 GHz.

THACO, a Test Facility for Characterizing the Noise Performance of Active Antenna Arrays

Abstract: This paper discusses an outdoor test facility for the noise characterization of active antenna arrays, using measurement results of array noise temperatures in the order of 50 K for a number of small aperture arrays. The measurement results are obtained by a Y-factor method with hot and a cold noise sources, with an absorber at room temperature as the hot load and the cold sky as the cold load. The effect of shielding the arrays by the test facility, with respect to noise and RFI from the environment, will also be discussed.

Window assembly having an antenna element overlapping a transparent layer and an adjacent outer region

Abstract: A window assembly for a vehicle has a transparent layer including a metal compound such that the transparent layer is electrically conductive. The transparent layer defines an area covering the window assembly. An outer region which is electrically non-conductive surrounds the area. The window assembly includes an antenna element including wire or transparent coating which overlaps the transparent layer and overlaps the outer region. The antenna element is configured to receive linearly or circularly polarized radio frequency (RF) signals. A feeding element is coupled to the antenna element for energizing the antenna element. The antenna element is capacitively coupled to the transparent layer. The transparent layer operates as a parasitic or active antenna element with respect to the antenna element.

Energy-efficient active antenna arrangement

Abstract: Energy-efficient active antenna arrangement (7) comprising an active antenna controller (5) for controlling TRX module sets comprising a master TRX module (2) and one or more slave TRX modules (3) and antenna elements (1,1'). The slave TRX modules (3) can be switched on/off by the active antenna controller (5) according to traffic load requirements, such that the output power of the antenna can be adjusted to reduce power consumption and the radiation pattern of the antenna remains substantially unchanged.

Method and device for compensating active antenna failure and active antenna equipment

Abstract: The invention provides a method and device for compensating active antenna failure and active antenna equipment. The method comprises the following steps: detecting respective digital beam forming (DBF) coefficient of multiple paths of receiving-transmitting channels in real time; when any receiving-transmitting channel is detected to fail, obtaining the current group of DBF coefficients of the multiple paths of receiving-transmitting channels and the corresponding failure mode information; optimizing the current group of DBF coefficients by a preset optimization algorithm, and calculating to obtain the first group of DBF coefficients which correspond to the current group of DBF coefficients and are more adaptive to the failure mode information; and according to the first group of DBF coefficients, updating the DBF coefficients of each path of receiving-transmitting channel. On the premise of requiring no mass preliminary computation work, the embodiment of the invention is characterized in that the active antenna can automatically solve to obtain an optimized DBF coefficient value, and the DBF coefficient value is automatically distributed to each receiving-transmitting channel so as to regulate the performance of the whole active antenna equipment and lower influence on the performance of the active antenna by the failed receiving-transmitting channels.

Integrated active antenna radiator

Abstract: The invention discloses an integrated active antenna radiator. The integrated active antenna radiator is characterized by comprising a substrate and radiating fins which are produced on one surface of the substrate, wherein the other surface of the substrate is provided with at least one active module mounting hole; and the radiating fins are arranged corresponding to the active module mounting hole. The integrated active antenna radiator has the advantages of bringing heat dissipation effect in a limited space into effect to the greatest extent, enhancing the water-proof effect of an active antenna, greatly reducing production cost and the like.

Slot antenna for frequency switchable active antenna

Abstract: Annular slot antenna having dual port and dual band which is suitable for use in the feed-back path of an oscillator resulting in an active antenna configuration by using the modern MIC and MMIC fabrication technology, compact light weight, and low cost active antenna are realized The proposed antenna is designed to radiate and transmit equal amounts of power The return loss of the proposed antenna is higher than that desired for one-port antenna application at the desired dual-band frequencies The antenna is fabricated on one side of a Neltec substrate (∊ r =33 and thickness = 0762 mm) and the microstrip feeding line is fabricated on the opposite side of the board The antenna was designed to operate at WLAN bands centered at 24 and 52GHz The simulated and measured results show fairly good agreement The measured return losses were found 205 dB at 24 GHz and 139 dB at 52GHz while simulated return losses were 936 dB at 24 GHz and 3135 dB at 52 GHz The radiation pattern is approximately omnidirectional at both frequencies in H-plane

A low-noise amplifier using subthreshold operation for GPS-L1 RF receiver

Abstract: This paper presents a low power low-noise amplifier (LNA) with subthreshold operation for Global Position System (GPS) L1-band radio frequency (RF) receiver using a 0.18 um CMOS process. An inductively degenerated cascode topology with a single ended to differential conversion using capacitive coupling compensation is applied to the LNA structure. The LNA has two tunable gain sates to support either a passive or an active antenna using a switchable resistive load. While drawing 1.07mA current from a 1.8V voltage supply, this LNA achieves a noise figure of 2.52dB and 3.7dB at the high and low gain states, respectively, a maximum voltage gain of 18.75dB, a S11 less than −10dB, and an IIP3 larger than −19.86dBm.

Wide-band 5-channel radio monitoring and super-resolution direction-finding mobile station system

Abstract: The invention provides a wideband five-channel wireless monitoring and super-resolution direction-finding mobile station system, which comprises a vertical-polarization passive/active direction-finding antenna array, an electrical rotary switching unit, an RF amplifier module, a five-channel direction-finding receiver, a monitoring direction-finding processing module, a computer system, a medium short wave monitoring antenna, an ultra-short wave monitoring antenna, a microwave monitoring antenna, and a monitoring receiver The wideband five-channel wireless monitoring and super-resolution direction-finding mobile station system has the advantages of modularized combination, light weight structure, good flexibility, and strong invisibility By adopting the spatial spectrum estimation super-resolution direction-finding technique and the DSP digital signal processing technique, the system can effectively identify a plurality of co-channel signals appearing simultaneously and improve the angle estimated precision, the angle resolution and the precision other related parameters of the spatial signals in a system processing wide band The passive/active antenna array is adopted to solvethe mutual coupling between the antenna array cells to eliminate the coupling and the phase ambiguity among element antennae The five antenna cells sample simultaneously to ensure synchronization, fastness, accuracy, strong interference resistance, and wide dynamic application range

Gain-enhanced distributed amplifier-based CRLH-leaky wave antenna for quasi-resonant power recycling scheme

Abstract: A distributed amplifier combined with CRLH-leaky wave antennas (LWAs) for a new resonant type power recycling scheme is proposed. By connecting a closed loop to the LWA on the drain side of the distributed amplifier, we can obtain gain enhancement compared to the one directly terminated without the loop. Such enhancement fluctuates with respect to the frequency. At some specific frequencies, the enhancement reaches a maximum. The phenomenon will be explained theoretically and validated through the measurement and simulation in this paper.

Self-oscillating dual-ring active integrated antenna

Abstract: By directly integrating an n-channel hetero-junction field effect transistor (FET) into a dual-ring radiator, a self-oscillating dual-ring active integrated antenna is proposed and demonstrated in this paper. The proposed active antenna, designed at 5.267 GHz, features an EIRP of 18.375 dBm, DC-to-RF conversion efficiency of 31.3%, and phase noise of −112.6 dBc/Hz at a 1-MHz offset from the carrier. With the aid of Agilent ADS and Ansoft HFSS, the oscillation frequency as well as the output oscillation power of the proposed dual-ring active antenna can be predicted. The design methodology, experimental setup, simulation and experimental results are discussed in this paper.

Signal receiving method of active antenna and signal receiver

Abstract: The invention provides a signal receiving method of an active antenna and a signal receiver. More than one preset local frequency is adopted to respectively carry out down-conversion on more than one radio frequency signal from an active antenna vibrator; more than one middle-frequency signal with the same frequency difference is obtained; more than one intermediate frequency signal is combined to obtain an analog combination signal; the analog combination signal is subjected to analog to digital conversion to obtain a digital combination signal; more than one preset extraction frequency is adopted to respectively carry out complex multiplication operation for the digital combination signal; and more than one preset extraction frequency is adopted to respectively carry out complex multiplication operation for the digital combination signal to obtain more than one target signal. According to the signal receiving method of an active antenna and the signal receiver provided by the invention, only one ADC (analog to digital converter) needs to be adopted to carry out analog to digital conversion for the combined signal so as to save a plurality of ADCs and lower the manufacture cost and the power consumption of the signal receiver.

Tunable Stacked Circular Patch Microstrip Antenna

Abstract: A Gunn diode loaded stacked circular patch antenna is proposed and analyzed It is found and threshold voltage of Gunn diode controls the performance of the antenna Various tunable frequency bands are obtained by selecting suitable bias voltage while antenna topology remains unchanged Antenna properties like return loss, in impedance, voltage standing-wave ratio (VSWR), bandwidth, etc, are calculated with the proposed model

Delay control in wide band Front-End components for multi-role/multi-domain phased-array systems

Abstract: In the framework of a bilateral Research Programme between Italy and Sweden MoDs (M-AESA), one of the main objective was the feasibility in terms of design dominance of analog Time Delay control in AESA Front-End. The need of managing the antenna beam-steering in terms of Time Delay, instead of phase-shifting, is due to the necessity of wide Instantaneous Bandwidth Requirement at System level. In this paper a solution which foresees the integration of the needed time delay both inside the TRMs and inside the RF Beam Forming Network is presented. In particular the feasibility evaluation has been performed by including smaller bits for Time Delay control in a GaAs chip (Core Chip) within the wide band TRM, to allow the amplitude and Delay control on each radiating element of the active antenna. As regards the higher bits, they have been included in a single True Time Delay component suitable for analog beam-forming network applications at sub-array/antenna level. It is worth to underline the added value of the solution directly applied on wide band components. The last, but not the least, challenging requirement was the size constraints, due to the X-Band array lattice. To do this, standard technologies for the integration solution (LTCC) and also for the chipset (pHEMT GaAs) at TRM and TTD level have been used. The high integration solutions for TRM and TTD component, the obtained performances, their compliance with design expectations shall be presented.