Showing papers on "Ka band published in 2002"

Astromesh™ deployable reflectors for ku- and ka-band commercial satellites

Abstract: The potential for the AstroMesh deployable mesh reflectors to support Ku- and Ka-band commercial satellite missions is investigated. The focus of the work is on predicting reflector gain/loss for 6-meter aperture point designs operating at 14 GHz and 30 GHz. The use of RMS surface errors from both systematic and random sources for gain/loss estimates via Ruze is shown to be accurate, and grating lobe performance for the systematic components is shown to be acceptable. Mesh reflectivity performance is given and total loss estimates for viable Ku- and Ka-band point designs are presented.

A single-chip 24 GHz receiver front-end using a commercially available SiGe HBT foundry process

Abstract: The authors have demonstrated a fully integrated receiver frontend addressing the ISM-Band at 24 GHz utilizing a standard SiGe HBT MMIC process with a relaxed emitter scaling of 1.2 /spl mu/m, for the first time. Extremely compact circuit design and layout techniques are applied to a mature Si/SiGe technology, resulting in a low-cost integrated circuit enabling consumer-oriented systems at Ka band. The integrated components are a preamplifier, a mixer with an IF buffer and a local oscillator. The conversion gain is determined to be 16.3 dB for an intermediate frequency of 100 MHz.

Near-field reflectivity and antenna boresight gain corrections for millimeter-wave atmospheric radars

Abstract: Millimeter-wavelength (MMW) cloud radars operating at Ka band (35 GHz) and W band (95 GHz) are popular atmospheric research tools because they are compact, have low prime power requirements, and are highly sensitive to small hydrometeors. In order to maximize sensitivity, ground-based systems use large diameter high-gain antennas. However, these antennas have substantial far-field distances as large as several kilometers. The far-field distance is defined as rf = 2D2/λ, where D is the antenna diameter and λ is the radar wavelength. In the Fresnel region, where 0.62D3/λ < r < rf, the antenna gain and pattern shape vary significantly with distance. Processing radar measurements obtained in the Fresnel region using the conventional radar equations gives erroneous results because these relationships assume far-field antenna characteristics. Correction factors are needed to account for the radar response to targets that lie in the near field. This paper provides correction factors for responses to tar...

Highly Selective Microstrip Bandpass Filters in Ka-Band

Abstract: Highly selective microstrip bandpass filters in Ka-band are developed by suitably inserting the attenuation poles in an edge-coupled structure. The attenuation poles at the high and low passband edges are introduced by adding a capacitively coupled gap and tapped open stubs in the conventional microstrip edge-coupled filter. In this study, the improved filters with center frequencies at 28 GHz and 38 GHz are fabricated on Teflon and Al2O3 substrates. Both filters have better selectivity and occupy the same area when compared with the conventional edge-coupled filter.

Characteristics of Ka band waveguide using electromagnetic crystal sidewalls

Abstract: Electromagnetic crystal structures have been used as sidewalls in special waveguides for the frequency range 30 to 40 GHz. They have the effect of substituting high impedance surfaces in place of the normal conducting metal sidewalls. The objectives in so doing are to obtain uniform electric field across the width of the waveguide and to force the wave in the guide to adopt the nature of a TEM wave. The measured insertion loss of Ka band waveguides is found to be low. The dependence of transmission phase on the center frequency of sidewall resonance has been measured and indicates that tunable sidewall resonance will provide simple and low loss phase shifting systems.

Simulation of the performance of a Ka-band VSAT videoconferencing system with uplink power control and data rate reduction to mitigate atmospheric propagation effects

Abstract: The purpose of this paper is to evaluate the impact of propagation effects at 20/30 GHz on the performances of the radio interface of a VSAT videoconferencing system and to demonstrate the interest to implement Fade Mitigation Techniques in order to improve the link availability. Specifications and system requirements of the VSAT network are briefly described. System performances of the physical layer are simulated using time-series data measured with the ESA's OLYMPUS satellite. The simulations enable to implement and optimize Up-Link Power Control and Data Rate Reduction, and to assess the related link performance improvement. Moreover, the introduction of propagation data sets allows to have a better idea of some system parameters which directly impact on the quality of service such as the switching rate or the link availability that such a system should have when deployed in operational conditions. Copyright (C) 2002 John Wiley Sons, Ltd.

High-power photonic microwave generation at K- and Ka-bands using a uni-traveling-carrier photodiode

Abstract: A K- to Ka-band photonic microwave generator (PMG) consisting of a uni-traveling-carrier photodiode (UTC-PD) and a monolithically integrated bias circuit utilizing a 1/4-wavelength coplanar waveguide is presented. The device exhibits a high-saturation-output power of +14 dBm at 26 GHz for a bias voltage of -4 V. The output power is almost constant within a frequency range from 23 to 29 GHz. The 3-dB down bandwidth of the generator is as wide as 20 GHz, which is in good agreement with the circuit model calculation. Two types of devices, one with and one without a dc-cut capacitor, exhibit almost the same input-output characteristics. The device for the operation in the 38-GHz band is also fabricated, and it shows a maximum millimeter-wave (mm-wave) output power of +9 dBm. The PMG is suitable for the broad-band high-output fiber-radio applications.

The Cassini Ka-band gravitational wave experiments

Abstract: Cassini, a joint American/European interplanetary scientific mission to Saturn, will be continuously and coherently tracked for 40 days during its solar oppositions in the next three years, starting on 26 November 2001. Doppler tracking searches for gravitational waves in the millihertz frequency band will be performed by using newly implemented Ka-band (≈32 GHz) microwave capabilities on the ground and onboard the spacecraft. Use of the Ka-band coherent microwave link will suppress solar plasma scintillations to levels below those identified by remaining instrumental noise sources, making the Cassini Doppler tracking experiments the most sensitive searches for gravitational waves ever attempted in the millihertz frequency band. This paper provides a short review of the Doppler response to gravitational radiation, the noise sources and their transfer functions into the Doppler observable and estimates of the anticipated Cassini Doppler tracking sensitivities to gravitational radiation.

Comparison of Multiple Rain Attenuation Models with Three Years of Ka Band Propagation Data Concurrently Taken at Eight Different Locations

Abstract: In June 1996, Working Party 3M of the ITU-R presented research comparing the estimations of 10 rain attenuation models with the 186 station years of earth-space propagation data contained within the ITU-R database known as DBSG5. Now, twenty-one station years of new data taken exclusively in the Ka band (20.185 GHz and 27.505 GHz) across North America are measured against many of those same models. Results are presented both in terms of error statistics as well as in comparison to the ITU database results.

Ka-band aeronautical satellite communications experiments using COMETS

Abstract: This paper describes the results of evaluation tests of an aeronautical satellite communications experiments system in the Ka-band using Japan's communications and broadcasting engineering test satellite (COMETS). An active phased-array antenna with an open-loop satellite tracking capability operating in the Ka-band was installed just behind the passenger window of an airplane to receive a satellite signal. The propagation measurements showed that the received signal power was stable within a signal-power variation of 1 dBp-p while the airplane was cruising at 600 km/h. At specific directions of the antenna, the radiowave reflected from the wing of the airplane was measured to be 18.5 dB lower in power compared with the line-of-sight signal. To confirm the designed link budget, the multibeam antenna pattern of COMETS' on-board antenna was measured while the airplane flew across two antenna beams. The antenna pattern matched the one measured in a ground test before launch. Two binary phase-shift keying (BPSK) modems, one for pilot-assisted coherent detection and the other for multiple-symbol differential detection, were used to measure the bit-error rate (BER). The measured received signal energy per bit per noise power density (E/sub b//N/sub 0/) at a BER of 10/sup -4/ showed only a small degradation of about 1 dB from that measured in a translator loop-back test.

Frequency estimation for low earth orbit satellites

Abstract: Low Earth Orbit (LEO) satellites have received increased attention in recent years. They have been proposed as a viable solution for remote sensing, telemedicine, weather monitoring, search and rescue and communications to name a few applications. LEO satellites move with respect to an earth station. Thus, the station must be capable of tracking the satellite both spatially and in frequency. In addition, as the spectrum becomes more congested, links are being designed at higher frequencies such as Ka band. These frequencies experience larger attenuations and therefore the system must be capable of operating at low signal to noise ratios. In this dissertation we report on the research conducted on the following problems. Firstly, we study the estimation of the frequency of a sinusoid for the purpose of acquiring and tracking the frequency of the received signal. Secondly, we propose the use of the frequency measurements to assist the spatial tracking of the satellite. The highly dynamic environment of a LEO system, combined with the high Ka band frequencies result in large Doppler rates. This limits the available processing time and, consequently, the fundamental resolution of a frequency estimator. The frequency estimation strategy that is adopted in the thesis consists of a coarse estimator followed by a fine estimation stage. The coarse estimator is implemented using the maximum of the periodogram. The threshold effect is studied and the derivation of an approximate expression of the signal to noise ratio at which the threshold occurs is examined. The maximum of the periodogram produces a frequency estimate with an accuracy that is Ο(N⁻¹), where N is the number of data samples used in the FFT. The lower bound for the estimation of the frequency of a sinusoid, given by the Cramer-Rao bound (CRB), is Ο(N⁻³⁄²) . This motivates the use of a second stage in order to improve the estimation resolution. A family of new frequency estimation algorithms that interpolate on the fractional Fourier coefficients is proposed. The new estimators can be implemented iteratively to give a performance that is uniform in frequency. The iterative algorithms are analysed and their asymptotic properties derived. The asymptotic variance of the iterative estimators is only 1.0147 times the asymptotic CRB. Another method of refining the frequency estimate is the Dichotomous search of the periodogram peak. This is essentially a binary search algorithm. However, the estimator must be padded with zeroes in order to achieve a performance that is comparable to the CRB. An insight into this is offered and a modified form that does not require the zero-padding is proposed. The new algorithm is referred to as the modified dichotomous search. A new hybrid technique that combines the dichotomous search with an interpolation technique in order to improve its performance is also suggested. The second research mm was to study the possibility of applying the frequency measurements to obtain spatial tracking information. This is called the frequency…

Highly efficient generation of subnanosecond microwave pulses in Ka-band relativistic BWO

Abstract: This paper presents the results of investigations of the mode of nonsteady-state oscillations with a short-time power burst which is characteristic of the initial stage of the transient process in a backward wave oscillator when the beam operating current is far in excess of the starting current. Numerical simulations have yielded the conditions under which the efficiency of the power transfer from an electron beam with a particle energy of 300 keV, a current of 2 kA, and a duration of 1 ns into a microwave pulse containing 8-10 high-frequency field periods approaches 90%. Experimentally, it has been demonstrated that the production of pulses like these with a duration of 200-250 ps, a power of up to /spl sim/400 MW, and a central frequency of about 38 GHz is feasible.

A new satellite repeater amplifier characterization system for large bandwidth NPR and modulated signals measurements

Abstract: Power consumption and dissipation of satellite payloads for space telecommunication systems are mainly due to power amplifiers. To increase system capacity with limited bandwidth, multicarrier operations are required. Linearity is specified to limit the signal distortion by the nonlinear power amplifiers. In order to minimize power consumption under those linearity requirements, accurate measurements have to be performed. The NPR is well known as the figure of merit for the intermodulation distortion performance of amplifiers in telecommunications. In this paper, the development of an accurate large bandwidth NPR measurement system is presented. It enables characterizations up to Ka band (17-21 GHz and 27-31 GHz for space telecommunications applications with typically 250 MHz bandwidth). Measurements made on power amplifiers have been used to optimize operating conditions.

Ka-band DBF terminal concepts for broadband satellite communications

Abstract: Results of a concept study dealing with a smart Digital Beam Forming (DBF) satellite terminal in Ka-band are presented. The objective of this study was to investigate systems, concepts and technologies for active DBF terminal antennas operating with future broadband satellite systems. The results were intended and are now being used as a basis for an ongoing project dealing with the development and realization of a DBF terminal demonstrator.Conformal antennas, discrete mode matching, numerical methods, network analysis

Design, Implementation and Measurements of Ka-band Waveguide-to-microstrip Transitions

Abstract: A low-loss broadband waveguide-to-microstrip transition has been developed successfully. The design procedure is based on the achievement of a matched impedance probe through the use of a high impedance line and a quarter wavelength transformer. The device has been constructed and measurements are shown.

Adaptive power and rate control for satellite communications in Ka band

Abstract: Adaptive power and rate control for efficient use of satellite channels in the Ka band are considered. Fading due to rain is modeled as a log-normally distributed, autoregressive process with known statistics. Adaptation policies based on MMSE channel estimation are designed taking into account the effect of channel estimation errors in an optimal manner so as to satisfy the required outage probability for given fading dynamics. Analytical results show average power savings or average bit rate increase that are available from adaptive techniques. It is demonstrated that a large improvement over a non-adaptive system is available provided an appropriately designed adaptation scheme that makes use of the channel fading statistics. Finally, practical methods based on adaptive modulation level selection in a fixed-bandwidth system are evaluated analytically in terms of average bandwidth efficiency.

Characteristics of rain fading on Ka-band satellite-earth links in a Pacific maritime climate

Abstract: Characteristics of rain-induced attenuation at Ka-band measured over a four-year period (1994-1997) with the advanced communications technology satellite (ACTS), Vancouver, BC, Canada, are reported. Event-based analyses of fading are performed and examples of the instantaneous 30/20-GHz frequency-scaling ratio are presented. Long-term cumulative statistics of rain rate as derived from rain-gauge measurements, along with annual attenuation statistics at 20 and 30 GHz, are provided. Finally, attenuation statistics are compared with the ITU-R model and aspects related to local climatic characteristics are considered, aiming to improve the predictions of attenuation due to rain.

1 and 2 watt MMIC power amplifiers for commercial K/Ka-band applications

Abstract: Two ICs, specifically designed for commercial applications at K/Ka-band frequencies, are presented. These ICs provide 1 and 2 watts of linear power respectively, gain levels of typically 17 dB and a power added efficiency of 25% at the 1 dB gain compression point. While the RF performance parameters are not state-of-the-art, these compact chips establish new levels for power density, Le. the ratio of output power to chip area. This figure of merit is particularly important for the cost sensitive commercial market.

Ka-band waveguide-to-microstrip transition design and implementation

Abstract: A low-loss broadband waveguide-to-microstrip transition has been developed successfully. The design procedure is based on the achievement of a matched impedance probe through the use of a high impedance line and a quarter wavelength transformer. This device is used in Ka-band systems. INTRODUCTION RF subsystems of the new Ka-bands systems (e.g., LMDS: Local to Multipoint Distribution System) require low-loss waveguide as passive components (e.g., RF filters and diplexers) technology. However the active subsystems are usually realized in MMIC (Monolithic Microwave Integrated Circuits) or hybrid MIC (Microwave Integrated Circuits) technologies. In many cases microstrip lines are the preferred energy transmission structures between these subsystems and the RF subsystem. Therefore a low-loss waveguide-to-microstrip transition is required. Several design approaches exist [1],[2]. In this paper a compact design leading to broadband low-loss waveguide-to-microstrip transition is presented. The method is based on a probe that extends naturally from a microstrip line [I]. The design approach is developed in the context of a particular design for a WR28 waveguide and SOR-microstrip line supported by CuClad substrate (~ ,=2 .17 , H=0.254 mm) for a frequency band from 27 GHz up to 35 GHz. Two transitions have been constructed and measured showing excellent performances. DESIGN The transition consists of an extension of a printed microstrip circuit through an aperture in the broad wall of a short-circuited waveguide as depicted in figure l(a). The.meta1 strip supported by the substrate couples the energy of the TElo mode of the waveguide and the energy of the quasi-TEM mode of the microstrip line in a similar way as a coaxial probe in a waveguide-to-coaxial transition. The aperture of the waveguide must be as small as possible in order not to perturb the field distribution in the waveguide. The maximum power transmission is reached when the microstrip line is matched at the feed point of the probe. 0-7803-733@8/02 $ 1 7 . 0 0 0 2 ~ I E E E 404 The electromagnetic behavior of the probe has been analyzed with a finite element electromagnetic analysis tool (Maxwell 3D Electromagnetic Simulator). The frequency variation of the reflection coefficient at the feed point depends on,the probe length (L), the distance of the waveguide short-circuit from the probe (D), and the probe width (W). In order to obtain a broadband design, i.e., to minimize the mentioned frequency variation, a parametric analysis of the reflection coefficient at the feed point with respect to the above-mentioned parameters has been realized. The optimized reflection coefficient is calculated through the analysis of the structure depicted in figure I(a), followed by a translation of the reference plane of the microstrip line port to the probe feed point. This analysis was performed for the WR28 waveguide and using CuClad substrate. The optimum values for L, D and W were thus obtained. The reflection coefficient of the optimized geometry is shown in figure 2. In order to obtain a matched structure a high-impedance transmission line (that simulates an inductor in series with the probe) is placed after the probe as shown in figure I(b). This structure was analyzed and the reflection coefficient obtained is presented in figure 3. It can be seen that the reflection coefficient is almost real, and can be easily matched to a 5OR-microstrip line with a quarter wavelength transformer. The final structure is shown in figure l(c). The HFSS simulation of the final transition is presented in figure 4. MEASUREMENTS Two transitions were fabricated and connected back-to-back through a 14 mm long microstrip line in a test-fixture. Figure 5 shows the measured insertion-loss and returnloss. The maximum insertion-loss is 0.95 dB and the minimum return-loss is 18 dB from 27 GHz up to 35 GHz. The estimated total insertion-loss for the WR28 waveguides of the test fixture was 0.2 dB, and the estimated insertion-loss for the 14 mm long microstrip line was 0.15 dB. Thus, after accounting for these losses, the obtained insertion-loss per transition is 0.3 dB approximately. CONCLUSION A Ka-band low-loss broadband waveguide-to-microstrip transition has been presented. The measured results of two transitions show excellent performance. The same design approach can be used to design optimum transitions at other frequencies and using other substrates. ACKNOWLEDGEMENTS The authors would like to thank Josd Mellado-Bema1 and Josd-Maria MonteroSerrano (both with Grupo de Microondas y Radar: GMR) for the construction and the assembly of the transitions. This work has been done under a contract between IKUSl S.A. (Spain) and GMR.

A radial waveguide power divider for Ka band phased array antennas

Abstract: A Ka band radial waveguide power divider has been designed for two-dimensional scanning phased array antennas. A measured result of 24% frequency bandwidth has been obtained for -20 dB return loss. Simulated results shows that the coupling amount of energy from a radial waveguide power divider to phase shifters can be controlled to meet the sidelobe requirements. Sensitivity studies for the coupling shows the tolerable amplitude errors for mass production. The coupling design results need to be verified by measurement results.

Ka-band extended interaction klystrons (EIKs) for satellite communication equipment

Abstract: Summary form only given. The VKA2400 series of Ka-band EIKs (extended interaction klystrons), for use in satellite communications, are described. They are fixed tuned, wide-bandwidth, permanent magnet focussed amplifiers operating in the 26.5 GHz to 35 GHz range. These flexible devices are capable of producing continuous wave power over 1000 W. Instantaneous bandwidths over 600 MHz are available. The unique multi-gap feature of the EIK significantly increases efficiency compared to a conventional single gap klystron at Ka-band. Electronic efficiencies (excluding collector depression) up to 28% have been achieved. Performance data on the Ka-band EIK is presented, enabling the system engineer to confidently characterize system performance.

Dynamic fade restoration in Ka‐band satellite systems

Abstract: Atmospheric precipitation can seriously affect the propagation of centimeter and millimeter electromagnetic waves. As a consequence, in some applications, it is necessary to make use of a fade countermeasure technique in order to satisfy the system availability and quality requirements. This study analyses the performance of a satellite-based system in geo-stationary orbit operating at 20 GHz, dynamically assigning the antenna directivity pattern to counteract tropospheric attenuation. The on-board power is spatially distributed over the covered region to minimize, at any time, the number of users undergoing outage because of the tropospheric attenuation. Both the aspects of broadcasting and telecommunication services are addressed. The reflector antenna of the system is supposed to be illuminated by a cluster of feeds driven by a set of excitation coefficients, continuously modified and optimized according to the meteorological information derived by processing METEOSAT satellite data and ECMWF (European Centre for Medium-Range Weather Forecasts) data. Copyright © 2002 John Wiley & Sons, Ltd.

Dual band antenna feed using an embedded waveguide structure

Abstract: A dual band antenna feed is made with an embedded waveguide structure to enable combining of Ka and Ku band signals without the need for an additional cavity-type filter. The antenna feed includes a Ka and Ku band interface section (22) with two Ka band vertical polarization waveguide sections (31) and (32), and a single Ku band waveguide section (34) which carries both vertical and horizontal polarization Ku band signals. The opposing walls (36-37) of the Ku band waveguide (34) carrying the vertical polarization Ku band signals are transitioned to step down from an input section (40) to successively smaller dimensioned sections (41-44), and then to step back up in successively larger dimensioned sections (45-47) to an output section (48). The two Ka band sections (31-32) are fed into openings in Ku band section.(46), on opposite sides of the opening for the Ku band transition section (45). The output section (48) then provides a combined Ka band vertical and Ku band horizontal and vertical signals. With the Ka-band waveguides (31-32) having ports (56-57) facing the antenna port for radiation on opposite sides of the Ku-band section (45) port, sufficient isolation will be provided between the Ka and Ku band signals without requiring an additional filter. A dielectric insert (FIG. 8A) may be included to improve performance characteristics of the antenna feed.

Ka-band coupled-cavity TWT amplifiers for military radar and commercial satellite communication

Abstract: Ka-band coupled-cavity traveling wave tube amplifiers have been developed for military radar applications requiring high power, moderate bandwidth and light weight. The design features and measured performance characteristics of these devices are presented. The technology advancements achieved in the radar programs are being leveraged to design Ka-band satellite communication amplifiers that surpass power limitations of existing solid state or helix TWT systems. The design features and expected performance of the communication amplifiers are presented. Recent development of a 3-D nonlinear time-domain simulation code, GATOR, is aiding the communication device design effort. The application of the codes to high efficiency amplifier design are illustrated.

Development of Ka-band 250W peak power Helix TWT

Abstract: Summary form only given. This paper describes the development of a Ka-band 250 W peak power helix traveling wave tube (TWT) for the gateway terminal of the next-generation Internet satellite communication system. NEC started the development of Ka-band microwave tubes for Japanese CS satellite programs in the early 1970's. Since then, the Ka-band microwave tubes development efforts has been carried out in order to achieve high performance, high reliability and cost reduction, and NEC developed the 100 W helix TWT in 1985 and the 150 W helix TWT in 1996. This time, we developed a new type of highly linear Ka-band TWT based on the many past experiences. The feature of this TWT is high output power more than 250 W (RF pulse) to achieve low distortion at the actual operating continuous output power level and high efficiency of 48% over 27.5-30.0 GHz. Although the output power of the conventional TWT for the satellite communication has usually specified only the continuous output power, this TWT has realized high continuous output power more than 150 W (-2.2 dB output back off) and RF pulse saturated output power more than 250 W, and low distortion at the actual operating continuous output power level. Moreover, such a high output power as 250 W was obtained in the same package size as the conventional TWT by improving the efficiency and decreasing the DC power consumption.

Detectable Rain Range of Spaceborne Ka-band Radar Estimated from TRMM Precipitation Radar Data

Abstract: A 14/35-GHz dual-wavelength radar is expected to be one of the next-generation spaceborne rain radars. The effect of rain attenuation at higher-frequency (35 GHz) radar with different minimum sensitivities was investigated through simulation. Based on the data taken by a single-wavelength (13.8 GHz) precipitation radar (PR) on board the Tropical Rainfall Measuring Mission (TRMM) satellite, the frequency distribution of the received power of the shorter-wavelength radar was first calculated through simulation. If the receiver minimum noise threshold is equivalent to about 10 dBZ, the missing fraction of near-surface rain due to attenuation degrading the signal below the noise threshold is about 15% over land and 3% over ocean compared to the PR.

A Ka-band perpendiculary-fed patch array for spatial power combining

Abstract: A Ka-band spatial power combining amplifier array employing a perpendicular feed structure is presented. The amplifier array utilizes perpendicularly-fed, aperture-coupled microstrip patch antennas with a unique feed structure for both the input and output antennas. This feed places the devices and antennas on separate planes, allowing for a smaller unit cell size, a simplified layout, and a minimum interaction between the devices and fields. A 7/spl times/7 passive and active amplifier array have been designed and fabricated at Ka-band. Experimental measurement results for both arrays are given.

A compact Ka-band 156 Mbps transceiver for a wireless LAN system using PTFE/FR-4 laminated MCMs

Abstract: A millimeter-wave radio access system has a number of features that makes it appealing as one approach to broadband communications. However, for a millimeterwave system to come into wide use, it must be miniaturized and the associated costs reduced. We have succeeded in realizing a compact 156 Mbps radio transceiver with a 38 GHz band optimizing RF architecture. We also adopted newly developed three-dimensional laminated MCMs using low cost plastic materials. It was confirmed in the initial experiments that this millimeter-wave wireless LAN equipment can cover a sufficient service area for broadband telecommunications in an indoor environment.