Showing papers on "Ka band published in 1988"
TL;DR: Fade countermeasure techniques that can be applied to Ka band satellite communication systems are reviewed and recommendations are made for operating systems.
Abstract: Fade countermeasure techniques that can be applied to Ka band satellite communication systems are reviewed. Considered in detail are diversity, adaptive forward error correction, fade spreading, up-link power control and adaptive TDMA. The techniques are compared for their effectiveness at Ka band, and recommendations are made for operating systems. The two important control techniques of fade detection and fade control are discussed in terms of their ease of implementation for each countermeasure technique. Details of a planned experiment to evaluate the application of fade countermeasures to VSAT networks via the Olympus satellite are presented.
34 citations
24 May 1988
TL;DR: In this paper, a K/Ka-band 3-bit GaAs monolithic microwave integrated circuit (MMIC) phase shifter using passive MESFET switching elements and is bidirectional.
Abstract: A description is given of a K/Ka-band 3-bit GaAs monolithic microwave integrated circuit (MMIC) phase shifter that uses passive MESFET switching elements and is bidirectional. The phase shifter uses high-pass/low-pass filter circuits in which MESFET off-state capacitances are incorporated as filter elements. This technique allows high-performance, broadband phase shifter response to be achieved. The K/Ka-band phase shifter uses MESFETs with the same characteristics as those used in amplifiers operating in the same band, for ease of future integration. The phase shifter operates from 18 to 40 GHz, with an average insertion loss of 9 to 10 dB. >
30 citations
TL;DR: Coherent mixing of optical radiation from a tunable CW dye laser and a stabilized HeNe laser was used to generate broadband microwave signals beyond the Ka band in FETs, HEMTs, and related devices as mentioned in this paper.
Abstract: Coherent mixing of optical radiation from a tunable CW dye laser and a stabilized HeNe laser was used to generate broadband microwave signals beyond the Ka band in FETs, HEMTs, and the related devices. Comparing with direct modulation of the light signal, this technique enhances photoconductivity and frequency stability.
18 citations
25 May 1988
TL;DR: In this paper, a description is given of monolithic GaAs p-i-n diode limiter circuits that have demonstrated 20 dB of variable attenuation at X-band and Ka-band while maintaining under 1.5:1 input voltage standing-wave ratio (VSWR).
Abstract: A description is given of monolithic GaAs p-i-n diode limiter circuits that have demonstrated 20 dB of variable attenuation at X-band and Ka-band while maintaining under 1.5:1 input voltage standing-wave ratio (VSWR). Insertion loss is 0.5-dB at 10 GHz and 1.4-dB at 36.5 GHz in the 0-mA bias condition. Passive limiting provides 7-dB of isolation at radio frequency (RF) powers up to 1.5 W (30% duty cycle). The process used to fabricate the variable attenuation limiter is compatible with FET circuits, allowing integration of other MMIC components on the same substrate for future single-chip radar front ends. Several of these circuits have been fabricated and RF tested. Fabrication, circuit design, and RF performance are discussed. >
17 citations
01 Jan 1988
TL;DR: In this paper, a 32 GHz six-element linear transmitter array utilizing monolithic microwave integrated circuit (MMIC) phase shifters and power amplifiers was developed, fabricated, and tested.
Abstract: A 32 GHz six-element linear transmitter array utilizing monolithic microwave integrated circuit (MMIC) phase shifters and power amplifiers was developed, fabricated, and tested. The array is composed of an RF signal distribution subsystem, a set of two MMIC carriers, and a patch antenna subsystem. The mean and standard deviation of the phase shift was 7.0+or-1.6% over the range 0 degrees to 300 degrees . The mean and standard deviation of output power at 1 dB gain compression was 13.6+or-0.3 dBm. Several externally tuned devices are capable of producing as much as 21.5 dBm with a power-added efficiency of 14.5% at 1-dB gain compression. The array provides a beamwidth of 7.5 degrees and has demonstrated acceptable beam steering over +or-8 degrees . >
16 citations
24 May 1988
TL;DR: In this paper, two distinct monolithic GaAs voltage-controlled oscillators (VCOs) are reported: a Gunn diode-based circuit and a FET-based one.
Abstract: Two distinct monolithic GaAs voltage-controlled oscillators (VCOs) are reported: a Gunn diode-based circuit and a FET-based circuit. The Gunn VCO design incorporates 14 Gunn diodes, a varactor diode, power combiner, matching network and bias on a single integrated chip. The Gunn oscillator has delivered 125 mW at 32 GHz and 70 mW at 40 GHz with up to 500 MHz of electrical tuning bandwidth. The FET circuit uses a 0.25- mu m*200- mu m GaAs MESFET; it has produced up to 20-mW output power at 35 GHz and over 300 MHz of voltage tuning bandwidth. >
14 citations
TL;DR: In this paper, two-stage and three-stage high-electron-mobility transistors (HEMTs) have exhibited state-of-the-art low-noise performance at millimeter-wave frequencies, with minimum noise figures of 1.7 and 1.9 dB, respectively.
Abstract: Quarter-micron-gate-length high-electron-mobility transistors (HEMTs) have exhibited state-of-the-art low-noise performance at millimeter-wave frequencies, with minimum noise figures of 1.2 dB and 32 GHz and 1.8 dB at 60 GHz. At Ka-band, two-stage and three-stage HEMT low-noise amplifiers have demonstrated noise figures of 1.7 and 1.9 dB, respectively, with associated gains of 17.0 and 24.0 dB at 32 GHz. At V-band, two stage and three-stage HEMT amplifiers yielded noise figures of 3.2 and 3.6 dB, respectively, with associated gains of 12.7 and 20.0 dB and 60 GHz. The 1-dB-gain compression point of all the amplifiers is greater than +6 dBm. The results clearly show the potential of short-gate-length HEMTs for high-performance millimeter-wave receiver application. >
14 citations
TL;DR: In this paper, a 14- to 37-GHz GaAs MMIC distributed power amplifier with three FETs of varying periphery, all capacitively coupled to the gate line, is discussed.
Abstract: A 14- to 37-GHz GaAs MMIC distributed power amplifier is discussed. The amplifier has three FETs of varying periphery, all capacitively coupled to the gate line. The drain of the FET nearest the output is capacitively coupled to the drain line to increase output power. A gain of 4 to 5 dB has been achieved from 14 to 37 GHz. Output power of 20 dBm or greater has been demonstrated at frequencies up to 33 GHz at 1-dB gain compression. A maximum 1-dB gain-compressed output power of 23.5 dBm (220 mW) has been measured at 36 GHz. The circuit is completely monolithic, with all bias and matching circuitry included on the chip. >
13 citations
25 May 1988
TL;DR: In this paper, a monolithic, single-stage high-electron-mobility transistor (HEMT) low-noise amplifier was developed for the 20-40 GHz band.
Abstract: A monolithic, single-stage high-electron-mobility transistor (HEMT) low-noise amplifier was developed for the 20-40-GHz band. This amplifier includes a single 0.25- mu m-gate-length HEMT active device with on-chip matching and biasing circuits. A gain of approximately 6 dB from 20 to 38 GHz, and a noise figure of approximately 5 dB from 26.5 to 38 GHz were measured. The chip size is 2.2 mm*1.1 mm. >
12 citations
11 Dec 1988
TL;DR: In this paper, the development of a family of brazed helix CW TWTs operating in the 27.5-30 GHz frequency band is described, along with a description of the main technological choices and operating parameters.
Abstract: The development of a family of brazed helix CW TWTs (continuous wave traveling wave tubes) operating in the 27.5-30-GHz frequency band is described. Results are given for a 200-W model now in the final stages of development, along with a description of the main technological choices and operating parameters. Power levels of 180 W CW have been obtained from a breadboard model, and 200 W will be easily obtained by minor adjustments to helix geometry. Destined for uplink earth station amplifiers in satellite communications applications, this tube has been optimized to meet the needs of civilian equipment users, offering high performance, low cost, high reliability, and long life expectancy. Preliminary tests confirm that the TWTs meet these criteria. >
10 citations
25 May 1988
TL;DR: In this paper, two 30 GHz-band monolithic microwave integrated circuit (MMIC) receiver modules needed to construct a Ka-band full-MMIC satellite transponder are described.
Abstract: Two 30-GHz-band monolithic microwave integrated circuit (MMIC) receiver modules needed to construct a Ka-band full-MMIC satellite transponder are described. Two different receiver configurations (an image-rejection type IR type) and a non-image-rejection type (NIR type) have been developed. The configuration of the NIR receiver is same as that of the IR type except for an external filter for image suppression between a low-noise amplifier and a mixer. The IR type is used for receivers incorporating the low-noise amplifier and mixer in one housing. The NIR type is used when the low-noise amplifier is installed separately from the receivers. Total system performance of a Ka-band receiver breadboard model incorporating the MMIC modules is reported. Test results indicate successful performance as a satellite receiver system. >
TL;DR: In this paper, a monolithic, single-stage HEMT low-noise amplifier was developed for the 20-40 GHz band, which includes a single 0.25- mu m-gate-length active device with on-chip matching and biasing circuits.
Abstract: A monolithic, single-stage HEMT low-noise amplifier has been developed for the 20-40-GHz band. it includes a single 0.25- mu m-gate-length HEMT active device with on-chip matching and biasing circuits. A gain of approximately 6 dB from 20 to 38 GHz and a noise figure of approximately 5 dB from 26.5 to 40 GHz were measured. Replacing the triangular gate profile by a mushroom gate profile in the amplifier increased the measured gain to 8 dB from 20 to 37 GHz and reduced the measured noise figure to 4 dB from 26 to 40 GHz. These are the best reported results for a MMIC amplifier over this bandwidth. The chip size is 2.2 mm*1.1 mm. The same amplifier was fabricated on pseudomorphic HEMT material with a triangular gate profile and achieved 7.5-dB gain across the 20-35-GHz bandwidth and a 6.0-dB noise figure from 26.5 to 40 GHz. The measured 1-dB compression powers at 30 GHz for the conventional and pseudomorphic HEMT amplifiers are 10 dBM and 11.5 dBM, respectively, when biased for maximum power. >
25 May 1988
TL;DR: In this article, high-power and high-gain Ka-band GaAs monolithic microwave integrated circuits (MMICs) were developed using a Be coimplantation technique.
Abstract: High-power and high-gain Ka-band GaAs monolithic microwave integrated circuits (MMICs) were developed using a Be coimplantation technique. At 29.5 GHz, an output power of 1 W with 4.2 dB gain was obtained for a 4.8-mm width MMIC. An intercept point of +42 dBm has been obtained from the third-order intermodulation distortion measurement. >
06 Nov 1988
TL;DR: An MMIC using a dual-gate MESFET (DGMF) for variable-power application in the 33 GHz band has been developed in this paper, where a single-stage amplifier demonstrated a linear gain of 91 dB and a dynamic range of 30 dB.
Abstract: An MMIC (microwave monolithic integrated circuit) using a dual-gate MESFET (DGMF) for variable-power application in the 33-GHz band has been developed A single-stage amplifier demonstrated a linear gain of 91 dB and a dynamic range of 30 dB A two-stage balanced amplifier provided a linear gain of 165 dB and maximum output power of 253 dBm at 33 GHz Minimal variations in the insertion phase and power-added efficiency of the DGMF as a function of second-gate control also were demonstrated This device may be suitable for application in phased-array systems for communications satellites and radar systems >
12 Sep 1988
01 Jun 1988
TL;DR: An experimental radio frequency link has been demonstrated to provide two-way communication between a remote user ground terminal and a ground-based Ka-band transponder.
Abstract: An experimental radio frequency link has been demonstrated to provide two-way communication between a remote user ground terminal and a ground-based Ka-band transponder. Bit-error-rate performance and radio frequency characteristics of the communication link were investigated.
TL;DR: In this article, the authors describe a national project aimed at securing for the UK a share of this future space market, which is the development by Marconi of an advanced 30/20 GHz space craft transponder for the Royal Signals and Radar Establishment (RSRE) at Defford as part of a programme sponsored by the British National Space Centre (BNSC).
Abstract: Frequency congestion in the established C-band (6/4 GHz) and Ku-band (14/11 GHz) used for fixed service satellite communications (satcom) will eventually impose a move to the Ka-band (30/20 GHz) space allocation Japan is already providing internal Ka-band satcom services via its national CS-2 spacecraft which was launched in 1983 CS-2 is the first of a number of national and international satellites carrying Ka-band payloads which are promised in the next five years to provide both fixed telecommunication services and inter-satellite relays Europe's first experimental venture into this new band will be starting in 1989 with the launch of the European Space Agency's (ESA) Olympus satellite This paper describes a national project aimed at securing for the UK a share of this future space market This is the development by Marconi of an advanced 30/20 GHz space craft transponder for the Royal Signals and Radar Establishment (RSRE) at Defford as part of a programme sponsored by the British National Space Centre (BNSC) This experimental transponder will provide the UK springboard for the development and testing of the many novel features of tomorrow's communications satellite payloads
11 Dec 1988
TL;DR: In this article, a computer-aided study has been conducted to determine the performance capability of Ka-band klystrons, with particular attention given to beam formation and confinement, thermal considerations, and RF circuit parameters.
Abstract: A computer-aided study has been conducted to determine the performance capability of Ka-band klystrons. Basic design parameters are explored, with particular attention given to beam formation and confinement, thermal considerations, and RF circuit parameters. Two illustrative conceptual designs are presented. One offers 250-kW peak power and 50% efficiency, and the other offers 3-kW peak output power and 340-MHz bandwidth. The possibility of extending average power output to over 2 kW is discussed. >
01 Apr 1988
TL;DR: In this article, the status and development of a number of these devices operating from Ku through Ka band are discussed along with anticipated potential applications, as well as their potential applications in future space communications subsystems.
Abstract: Future Space Communications subsystems will utilize GaAs Monolithic Microwave Integrated Circuits (MMIC's) to reduce volume, weight, and cost and to enhance system reliability. Recent advances in GaAs MMIC technology have led to high-performance devices which show promise for insertion into these next generation systems. The status and development of a number of these devices operating from Ku through Ka band will be discussed along with anticipated potential applications.
24 May 1988
TL;DR: In this paper, a 14 to 37 GHz monolithic microwave integrated-circuit (MMIC) distributed power amplifier was described, which has three FETs of varying periphery, all capacitively coupled to the gate line.
Abstract: A 14 to 37-GHz monolithic microwave integrated-circuit (MMIC) distributed-power amplifier is described that has three FETs (field-effect transistors) of varying periphery, all capacitively coupled to the gate line. The capacitor is inserted between the drain line and the drain of any FET seeing a low or negative impedance. This deceases drain line loading and increases the impedance at the drains. High total-FET-periphery can be accommodated, achieving higher output power. A 4-dB gain was achieved from 14 to 37 GHz. Output power of 20 dBm or greater has been demonstrated at frequencies up to 33 GHz at 1 dB compression. A maximum 1-dB compressed output power of 23.5 dBm (220 mw) has been measured at 26 GHz. The circuit is truly monolithic, with all bias and matching circuitry included on the chip. >
01 Jul 1988
TL;DR: A 20 W solid state amplifier was developed by the TRW Electronic Systems Group under NASA Contract NAS3-23266 as a proof-of-concept (POC) device in support of the Advanced Communications Technology Satellite (ACTS) program as discussed by the authors.
Abstract: Described are the characterization and testing of a 20 W solid state amplifier operating in the Ka band to be used in low cost experimental ground terminals. The amplifier was developed by the TRW Electronic Systems Group under NASA Contract NAS3-23266 as a proof-of-concept (POC) device in support of the Advanced Communications Technology Satellite (ACTS) program. Additional goals were development of high-power IMPATT devices and circulators, and multistage diode circuits, which are an integral part of the amplifier. The amplifier underwent acceptance testing at the NASA Lewis Research Center, Cleveland, Ohio. Characteristics measured include the output power of 42 dB m, gain of 30 dB, an injection-locking RF bandwidth of 260 MHz, and an overall direct current-to-radiofrequency (dc-to-RF) efficiency of 6.7 percent.
01 Oct 1988
TL;DR: In this paper, the Finite element method is used to compute the scattering matrix of waveguide structures with E or H plane discontinuities, which allows the analysis of bandpass filters and multiplexers in a very flexible way.
Abstract: The Finite element Method is used to compute the scattering matrix of waveguide structures with E or H plane discontinuities. This method allows the analysis of bandpass filters and multiplexers in a very flexible way including the effects of waveguide discontinuities as bends and junctions. A diplexer in Ka band has been designed and constructed. Several experimental results are presented.
15 Aug 1988
TL;DR: In this article, the results of an X/X/Ka-band feed design concept demonstration are presented to show the feasibility of adding a Ka-band beacon to the Mars Observer spacecraft Scale model radiation patterns were made and analyzed.
Abstract: The results of an X/X/Ka-band feed design concept demonstration are presented The purpose is to show the feasibility of adding a Ka-band beacon to the Mars Observer spacecraft Scale model radiation patterns were made and analyzed