Millimeter-Wave Multi-Port Front-End Receivers: Design Considerations and Implementation

This chapter covers recent achievements on the integrated 60 GHz millimeter-wave front-end receiver based on the multi-port (six-port) concept. For this purpose, the design procedure of a fully integrated 60 GHz multi-port (six-port) front-end receiver implemented on a thin ceramic substrate (εr = 9.9, h = 127 μm) using an miniature hybrid microwave integrated circuit (MHMIC) fabrication process is presented in detail. All components constituting the proposed front-end receiver including an 8 × 2 antenna array, a low-noise amplifier (LNA), a six-port circuit, and the RF power detectors are presented and characterized separately before they are integrated into the final front-end receiver prototype. The performance of the latter has been experimentally evaluated in terms of various M-PSK/M-QAM demodulations. The obtained demodulation results are very satisfactory (the constellation points for all considered M-PSK/M-QAM schemes are very close to the ideal locations), demonstrating and confirming the high ability of the proposed 60 GHz millimeter-wave six-port front-end receiver to operate as a high-performance quadrature demodulator, without any calibration, for modulation schemes up to 32 symbols

Comparative study of bolometric and non-bolometric switching elements for microwave phase shifters

The performance of semiconductor and high critical temperature superconductor switches is compared as they are used in delay-line-type microwave and millimeter-wave phase shifters. Such factors as their ratios of the off-to-on resistances, parasitic reactances, power consumption, speed, input-to-output isolation, ease of fabrication, and physical dimensions are compared. Owing to their almost infinite off-to-on resistance ratio and excellent input-to-output isolation, bolometric superconducting switches appear to be quite suitable for use in microwave phase shifters; their only drawbacks are their speed and size. The SUPERFET, a novel device whose operation is based on the electric field effect in high critical temperature ceramic superconductors is also discussed. Preliminary results indicate that the SUPERFET is fast and that it can be scaled; therefore, it can be fabricated with dimensions comparable to semiconductor field-effect transistors

High efficiency planar microwave antennas assembled using millimetre thick micromachine polymer structures

Communication systems at microwave and millimetre wave regimes require compact broadband high gain antenna devices for a variety of applications, ranging from simple telemetry antennas to sophisticated radar systems. High performance can usually be achieved by fabricating the antenna device onto a substrate with low dielectric constant or recently through micromachining techniques. This thesis presents the design, fabrication, assembly and characterisation of microstrip and CPW fed micromachined aperture coupled single and stacked patch antenna devices. It was found that the micromachining approach can be employed to achieve a low dielectric constant region under the patch which results in suppression of surface waves and hence increasing radiation efficiency and bandwidth. A micromachining method that employs photolithography and metal deposition techniques was developed to produce high efficiency antenna devices. The method is compatible with integration of CMOS chips and filters onto a common substrate. Micromachined polymer rims (SU8 photoresist) was used to create millimetre thick air gaps between the patch and the substrate. The effect of the substrate materials and the dimensions of the SU8 polymer rims on the performance of the antenna devices were studied by numerical simulation using Ansoft HFSS electromagnetic field simulation package. The antenna structures were fabricated in layers and assembled by bonding the micromachined polymer spacers together. Low cost materials like SU8, polyimide and liquid crystal polymer films were used for fabrication and assembly of the antenna devices. A perfect patch antenna device is introduced by replacing the substrate of a conventional patch antenna device with air in order to compare with the micromachined antenna devices. The best antenna parameters for a perfect patch antenna device with air as a substrate medium are ~20% for bandwidth and 9.75 dBi for antenna gain with a radiation efficiency of 99.8%. In comparison, the best antenna gain for the simple micromachined patch antenna device was determined to be ~8.6 dBi. The bandwidth was ~20 % for a microstrip fed device with a single patch; it was ~40 % for stacked patch devices. The best bandwidth and gain of 6.58 GHz (50.5%) and 11.2 dBi were obtained for a micromachined sub-array antenna device. The simulation results show that the efficiency of the antenna devices is above 95 %. Finally, a novel high gain planar antenna using a frequency selective surface (FSS) was studied for operation at ~60 GHz frequency. The simulation results show that the novel antenna device has a substantial directivity of around 25 dBi that is required for the emerging WLAN communications at the 60 GHz frequency band

Submillimeter satellite radiometer Final engineering report

All solid-state superheterodyne Dicke radiometer for submillimeter wavelength

Radiation pattern reconfigurable microfabricated planar millimeter-wave antennas

Els serveis de telecomunicacions i sistemes radar estan migrant a freqüències mil•limètriques (MMW), on es disposa d 'una major amplada de banda i conseqüentment d'una major velocitat de transmissió de dades. Aquesta migració requereix de l'ús de diferents tecnologies amb capacitat d'operar a la banda de freqüències mil•limètriques (30 a 300 Ghz), i més concretament en les bandes Ka (26,5 - 40GHz), V (50 – 75GHz) i W (75 – 110GHz). En moltes aplicacions i sobretot en aquelles on l'antena forma part d'un dispositiu mòbil, es cerca poder utilitzar antenes planes, caracteritzades per tenir unes dimensions reduïdes i un baix cost de fabricació. El conjunt de requeriments es pot resumir en obtenir una antena amb capacitat de reconfigurabilitat i amb un baix nivell de pèrdues en cada una de les bandes de freqüència. Per tal d'afrontar aquests reptes, les dimensions de les antenes mil•limètriques, juntament amb els tipus de materials, toleràncies de fabricació i la capacitat de reconfigurabilitat ens porten a l'ús de processos de microfabricació. L'objectiu d'aquesta tesis doctoral és l'anàlisi dels conceptes mencionats, tipus de materials, geometries de línia de transmissió i interruptors, en el context de les freqüències mil•limètriques, així com la seva aplicació final en dissenys d'antenes compatibles amb els processos de microfabricació. Finalment, com a demostració s'han presentat dissenys específics utilitzables en tres aplicacions a freqüències mil•limètriques: Sistemes de Comunicació per Satèl•lit (SCS) a la banda Ka, Xarxes d'àrea personal inalàmbriques (WPAN) a la banda V i sistemes radar per l'automoció a la banda W. La primera part d'aquesta tesis consisteix en l'anàlisi d'algunes tecnologies circuitals a freqüències mil•limètriques. S'han presentat els materials més utilitzats a altes freqüències (Polytetrafluoroethylene or Teflon (PTFE), Quartz, Benzocyclobuten polymer (BCB) i Low Temperature Co-fired Ceramic (LTCC)) i s'han comparat en termes de permitivitat i tangent de pèrdues. També s'inclou un estudi de pèrdues a altes freqüències en les principals línies de transmissió (microstrip, stripline i CPW). Finalment, es presenta un resum dels interruptors RF-MEMS i es comparen amb els PIN diodes i els FET. En la segona part, es presenten diferents agrupacions d'antenes amb la capacitat de reconfigurar la polarització i la direcció d'apuntament. S'han dissenyat dos elements base reconfigurables en polarització: CPW Patch antena i 4-Qdime antena. La primera antena consisteix en un element singular amb interruptors RF-MEMS, dissenyada per operar a les bandes Ka i V. La segona antena consisteix en una arquitectura composta on la reconfigurabilitat en polarització s'obté mitjançant variant la fase d'alimentació de cada un dels quatre elements lineals. La fase és controlada mitjançant interruptors RF-MEMS ubicats en la xarxa de distribució. L'antena 4-Qdime s'ha dissenyat per operar en les bandes V i W. Ambdós elements base s'han utilitzat posteriorment pel disseny de dues agrupacions d'antenes amb capacitat de reconfigurar l'apuntament del feix principal. La reconfigurabilitat es dur a terme utilitzant desfasadors de fase d'1 bit. La part final de la tesis es centra en les toleràncies de fabricació i en els processo de microfabricació d'agrupacions d'antenes mil•limètriques. Les toleràncies de fabricació s'han estudiat en funció dels error d'amplitud i fase en cada element de l'agrupació, fixant-se en les pèrdues de guany, error d'apuntament, error en l'amplada de feix, errors en el nivell de lòbul secundari i en l'error en la relació axial. El procés de microfabricació de les diferents antenes dissenyades es presenta en detall. Els dissenys de l'antena CPW Patch reconfigurable en polarització i apuntament operant a les bandes Ka i V, s'han fabricat en la sala blanca del Cornell NanoScale Science & Technology Facility (CNF). Posteriorment, s'han caracteritzat l'aïllament i el temps de resposta dels interruptors RF-MEMS, i finalment, el coeficient de reflexió, el diagrama de radiació i la relació axial s'han mesurat a les bandes Ka i V per les antenes configurades en polarització lineal (LP) i circular (CP).Telecommunication services and radar systems are migrating to Millimeter-wave (MMW) frequencies, where wider bandwidths are available. Such migration requires the use of different technologies with the capability to operate at the MMW frequency band (30 to 300GHz), and more specifically at Ka- (26.5 to 40GHz), V- (50 to 75GHz) and W-band (75 to 110GHz). For many applications and more concretely those where the antenna is part of a mobile device, it is targeted the use of planar antennas for their low profile and low fabrication cost. A wide variety of requirements is translated into a reconfiguration capability and low losses within each application frequency bandwidth. To deal with the mentioned challenges, the MMW antenna dimensions, together with the materials, fabrication tolerances and reconfigurability capability lead to microfabrication processes. The aim of this thesis is the analysis of the mentioned concepts, materials, transmission lines geometries and switches in the MMW frequencies context and their final application in antenna designs compatible with microfabrication. Finally, specific designs are presented as a demonstration for three MMW applications: Satellite Communication Systems (SCS) at Ka-band, Wireless Personal Area Network (WPAN) at V-band and Automotive Radar at W-band. The first part of this thesis consist to analyze some MMW circuit technologies. The four most used materials at MMW frequencies (Polytetrafluoroethylene or Teflon (PTFE), Quartz, Benzocyclobuten polymer (BCB) and Low Temperature Co-fired Ceramic (LTCC)) have been presented and compared in terms of permittivity (εr) and loss tangent (tanδ). An study of the main transmission lines attenuation (microstrip, stripline and CPW) at high frequencies is included. Finally, an overview of the RF-MEMS switches is presented in comparison with PIN diodes and FETS switches. The second part presents different polarization and beam pointing reconfigurable array antennas. Two polarization-reconfigurable base-elements have been designed: CPW Patch antenna and 4-Qdime antenna. The first consists of a single reconfigurable element with integrated RF-MEMS switches, designed to operate at Ka- and V-band. The second antenna presented in this thesis has a composed architecture where the polarization reconfigurability is obtained by switching the phase feeding for each of the four linear polarized elements in the feed network with RF-MEMS switches. The 4-Qdime antenna has been designed to operate at V- and W-band. The two base-elements have been used to design two beam pointing reconfigurable antenna arrays. Using phased array techniques, beamsteering is computed and implemented with 1-bit discrete phase-shifter. The final part of the thesis is focused into the fabrication tolerances and microfabrication process of Millimeter-wave antenna arrays. The fabrication tolerances have been studied as a function of the amplitude and phase errors presented at each elements array, focusing on the gain loss, beam pointing error, Half-Power Beamwidth (HPBW) error, sidelobe level error and axial ratio error. The microfabrication process for the designed antennas is presented in detail. Polarization- and pointing- reconfigurable CPW Patch antenna operating at Ka- and V- band have been fabricated in a clean-room facility at Cornell NanoScale Science & Technology Facility (CNF). The RF-MEMS switches isolation and time response have been characterized. Finally, the reflection coefficient, radiation pattern and axial ratio have been measured at Ka- and V-band for the fabricated antennas configured in Linear Polarization (LP) and Circular Polarization (CP)

Submillimeter sources for radiometry using high power Indium Phosphide Gunn diode oscillators

A study aimed at developing high frequency millimeter wave and submillimeter wave local oscillator sources in the 60-600 GHz range was conducted. Sources involved both fundamental and harmonic-extraction type Indium Phosphide Gunn diode oscillators as well as varactor multipliers. In particular, a high power balanced-doubler using varactor diodes was developed for 166 GHz. It is capable of handling 100 mW input power, and typically produced 25 mW output power. A high frequency tripler operating at 500 GHz output frequency was also developed and cascaded with the balanced-doubler. A dual-diode InP Gunn diode combiner was used to pump this cascaded multiplier to produce on the order of 0.5 mW at 500 GHz. In addition, considerable development and characterization work on InP Gunn diode oscillators was carried out. Design data and operating characteristics were documented for a very wide range of oscillators. The reliability of InP devices was examined, and packaging techniques to enhance the performance were analyzed. A theoretical study of a new class of high power multipliers was conducted for future applications. The sources developed here find many commercial applications for radio astronomy and remote sensing