$S$ - and $C$ -Band Ultra-Compact Phase Shifters Based on All-Pass Networks

Ultra-compact phase shifters are presented. The proposed phase-shifting circuits utilize the lumped element all-pass networks. The transition frequency of the all-pass network, which determines the size of the circuit, is set to be much higher than the operating frequency. This results in a significantly small chip size of the phase shifter. To verify this methodology, 5-bit phase shifters have been fabricated in the $S$ - and $C$ -band. The $S$ -band phase shifter, with a chip size of 1.87 mm $,times,$0.87 mm (1.63 mm $^{2}$), has achieved an insertion loss of ${hbox{6.1 dB}} pm {hbox{0.6 dB}}$ and rms phase-shift error of less than 2.8$^{circ}$ in 10% bandwidth. The $C$ -band phase shifter, with a chip size of 1.72 mm $,times,$0.81 mm (1.37 mm $^{2}$), has demonstrated an insertion loss of 5.7 dB $pm$ 0.8 dB and rms phase-shift error of less than 2.3 $^{circ}$ in 10% bandwidth.      

A Dual-Band Self-Oscillating Mixer for -Band and -Band Applications

A self-oscillating mixer that employs both the fundamental and harmonic signals generated by the oscillator subcircuit in the mixing process is experimentally demonstrated. The resulting circuit is a dual-band down-converting mixer that can operate in $C$ -band from 5.0 to 6.0 GHz, or in $X$-band from 9.8 to 11.8 GHz. The oscillator uses active superharmonic coupling to enforce the quadrature relationship of the fundamental outputs. Either the fundamental outputs of the oscillator or the second harmonic oscillator output signals that exists at the common-mode nodes are connected to the mixer via a set of complementary switches. The mixer achieves a conversion gain between 5–12 dB in both frequency bands. The output 1-dB compression points for both modes of the mixer are approximately $-{hbox{5 dBm}}$ and the output third-order intercept point for $C$ -band and $X$ -band operation are 12 and 13 dBm, respectively. The integrated circuit was fabricated in 0.13-$mu {hbox{m}}$ CMOS technology and measures ${hbox{0.525 mm}}^{2}$ including bonding pads.      

RF Power Measurements of InAlN/GaN Unstrained HEMTs on SiC Substrates at 10 GHz

Unstrained high-electron mobility transistors (HEMTs) were fabricated from InAlN/GaN on semi-insulating SiC substrates. The devices had 0.24-$muhbox{m}$ T-gates with a total width of $hbox{2} times hbox{150} muhbox{m}$. Final passivated performance values for these devices are $I_{max} = hbox{1279} hbox{mA/mm}$, $I_{rm DSS} = hbox{1182} hbox{mA/mm}$ , $R_{c} = hbox{0.43} Omega cdot hbox{mm}$, $rho_{s} = hbox{315} Omega/hbox{sq}$, $f_{T} = hbox{45} hbox{GHz}$, $f_{max({rm MAG})} = hbox{64} hbox{GHz}$, and $g_{m} = hbox{268} hbox{mS/mm}$. Continuous-wave power measurements at 10 GHz produced $P_{rm sat} = hbox{3.8} hbox{W/mm}$, $G_{t} = hbox{8.6} hbox{dB}$, and $hbox{PAE} = hbox{30}%$ at $V_{rm DS} = hbox{20} hbox{V}$ at 25% $I_{rm DSS}$ . To our knowledge, these are the first power measurements reported at 10 GHz for this material.      

High-Speed High-Isolation 2$, times ,$2 Fiber-Optic Switch for Wideband Radar Photonic Beamforming Controls

A new high-performance 2$, times ,$2 fiber-optic switch is designed and demonstrated for wideband radar photonic beamforming controls. The switch deploys two bulk acoustooptic deflectors (AODs) in an imaging free-space symmetric optical design that exploits image inversion control via a Dove prism to form a 2$, times ,$2 fully reversible low crosstalk noise high-speed switching structure. Experiments at the 1550-nm test wavelength show the switch to handle 0.5-W level optical input powers, $≪ {hbox{2.2-}}mu$s switching time, $≪ $2.6-dB fiber-to-fiber optical loss, better than 56-dB optical crosstalk levels, and $≪$0.2-dB polarization-dependent loss (PDL).      

Integrated Hydrogen-Sensing Amplifier With GaAs Schottky-Type Diode and InGaP–GaAs Heterojunction Bipolar Transistor

New hydrogen-sensing amplifiers are fabricated by integrating a GaAs Schottky-type hydrogen sensor and an InGaP–GaAs heterojunction bipolar transistor. Sensing collector currents ( $I_{rm CN}$ and $I_{rm CH}$) reflecting to $hbox{N}_{2}$ and hydrogen-containing gases are employed as output signals in common-emitter characteristics. Gummel-plot sensing characteristics with testing gases as inputs show a high sensing-collector-current gain $(I_{rm CH}/I_{rm CN})$ of $≫hbox{3000}$. When operating in standby mode for in situ long-term detection, power consumption is smaller than 0.4 $muhbox{W}$. Furthermore, the room-temperature response time is 85 s for the integrated hydrogen-sensing amplifier fabricated with a bipolar-type structure.      

CPW to Rectangular Waveguide Transition on an ${hbox{LiNbO}}_{3}$ Substrate

This paper presents transition from coplanar waveguide (CPW) to rectangular waveguide for $W$ -band (75–110 GHz) operations. The waveguide consists of a cosine-shaped fin extending from the upper waveguide wall onto the CPW signal electrode. The design features direct integration of the waveguide with opto-electronic devices on lithium niobate $({hbox{LiNbO}}_{3})$ for the applications of millimeter wave to optical signal processing. Simulations and measurements show that the model works very well over the entire $W$-band. Measurements of fabricated devices have yielded return loss of more than 10 dB and insertion loss of about 2.8 dB over the operating bandwidth.      

A Silicon-Germanium Receiver for X-Band Transmit/Receive Radar Modules

This work investigates the potential of commercially-available silicon-germanium (SiGe) BiCMOS technology for X-band transmit/receive (T/R) radar modules, focusing on the receiver section of the module. A 5-bit receiver operating from 8 to 10.7 GHz is presented, demonstrating a gain of 11 dB, and average noise figure of 4.1 dB, and an input-referred third-order intercept point $({hbox{IIP}}_{3})$ of $-$13 dBm, while only dissipating 33 mW of power. The receiver is capable of providing 32 distinct phase states from 0 to 360$^{circ}$ , with an rms phase error $≪ !{hbox{9}}^{circ}$ and an rms gain error $≪ ,$0.6 dB. This level of circuit performance and integration capability demonstrates the benefits of SiGe BiCMOS technology for emerging radar applications, making it an excellent candidate for integrated X-band phased-array radar transmit/receive modules.      

A 40–50-GHz SiGe 1 : 8 Differential Power Divider Using Shielded Broadside-Coupled Striplines

This paper presents a 1 : 8 differential power divider implemented in a commercial SiGe BiCMOS process using fully shielded broadside-coupled striplines integrated vertically in the silicon interconnect stackup. The 1 : 8 power divider is only 1.12 $,times,$1.5 mm$^{2}$ including pads, and shows 0.4-dB rms gain imbalance and $≪ {hbox{3}}^{circ}$ rms phase imbalance from 40 to 50 GHz over all eight channels, a measured power gain of ${hbox{14.9}} pm {hbox{0.6}}$ dB versus a passive divider at 45 GHz, and a 3-dB bandwidth from 37 to 52 GHz. A detailed characterization of the shielded broadside-coupled striplines is presented and agrees well with simulations. These compact lines can be used for a variety of applications in SiGe/CMOS millimeter-wave circuits, including differential signal distribution, miniature power dividers, matching networks, filters, couplers, and baluns.      

A Phase-Locked Loop With Injection-Locked Frequency Multiplier in 0.18-$mu{hbox{m}}$ CMOS for $V$ -Band Applications

In this paper, a novel CMOS phase-locked loop (PLL) integrated with an injection-locked frequency multiplier (ILFM) that generates the $V$-band output signal is proposed. Since the proposed ILFM can generate the fifth-order harmonic frequency of the voltage-controlled oscillator (VCO) output, the operational frequency of the VCO can be reduced to only one-fifth of the desired frequency. With the loop gain smaller than unity in the ILFM, the output frequency range of the proposed PLL is from 53.04 to 58.0 GHz. The PLL is designed and fabricated in 0.18-$mu{hbox{m}}$ CMOS technology. The measured phase noises at 1- and 10-MHz offset from the carrier are $-$ 85.2 and $-{hbox{90.9 dBc}}/{hbox{Hz}}$, respectively. The reference spur level of $-{hbox{40.16 dBc}}$ is measured. The dc power dissipation of the fabricated PLL is 35.7 mW under a 1.8-V supply. It can be seen that the advantages of lower power dissipation and similar phase noise can be achieved in the proposed PLL structure. It is suitable for low-power and high-performance $V$-band applications.      

Combined-Phase-Shift Waveguide Polarizer

A waveguide polarizer exploiting two different phase shift phenomena is presented in this letter. Iris-type discontinuities are in fact introduced in a waveguide structure having different propagation constants for the two principal polarizations. In this way, the required 90 $^circ$ differential phase shift is obtained combining the iris phase shift with the waveguide one. Several operative conditions arise from the combination of the two contributions. This approach has been used to design a broadband waveguide polarizer for the $C$-band antenna feed system of the Sardinia Radio Telescope with ${-}$ 40 dB reflection coefficients and a ${-}$35 dB cross polarization level in a 30% bandwidth.      

180$^{circ}$ and 90$^{circ}$ Phase Shifting Networks With an Octave Bandwidth and Small Phase Errors

A new phase shifting network for both 180 $^{circ}$ and 90 $^{circ}$ phase shift with small phase errors over an octave bandwidth is presented. The theoretical bandwidth is 67% for the 180$^{circ}$ phase bit and 86% for the 90$^{circ}$ phase bit when phase errors are $pm 2^{circ}$. The proposed topology consists of a bandpass filter (BPF) branch, consisting of a LC resonator and two shunt quarter-wavelength transmission lines (TLs), and a reference TL. A theoretical analysis is provided and scalable parameters are listed for both phase bits. To test the theory, phase shifting networks from 1 GHz to 3 GHz were designed. The measured phase errors of the 180$^{circ}$ and the 90$^{circ}$ phase bit are $pm 3.5^{circ}$ and $pm 2.5^{circ}$ over a bandwidth of 73% and 102% while the return losses are better than 18 dB and 12 dB, respectively.      

Ultra-High Power and Efficiency Space Traveling-Wave Tube Amplifier Power Combiner With Reduced Size and Mass for NASA Missions

In the 2008 IEEE Microwave Theory and Techniques Society International Microwave Symposium Digest version of our paper, recent advances in high power and efficiency space traveling-wave tube amplifiers for NASA's space-to-Earth communications are presented. The RF power and efficiency of a new $K$-band amplifier are 40 W and 50% and that of a new $Ka$-band amplifier are 200 W and 60%. An important figure-of-merit, which is defined as the ratio of the RF power output to the mass (W/kg) of a traveling-wave tube (TWT), has improved by a factor of 10 over the previous generation $Ka$-band devices. In this paper, a high power high efficiency $Ka$ -band combiner for multiple TWTs, based on a novel hybrid magic-T waveguide circuit design, is presented. The measured combiner efficiency is as high as 90%. In addition, at the design frequency of 32.05 GHz, error-free uncoded binary phase-shift keying/quadrature phase-shift keying (QPSK) data transmission at 8 Mb/s, which is typical for deep-space communications, is demonstrated. Furthermore, QPSK data transmission at 622 Mb/s is demonstrated with a low bit error rate of ${hbox{2.4}}times {hbox{10}}^{-8}$, which exceeds the deep-space state-of-the-art data rate transmission capability by more than two orders of magnitude. A potential application of the TWT combiner is in deep-space communication systems for planetary exploration requiring transmitter power on the order of a kilowatt or higher.      

Improved Bounds on the $L(2,1)$-Number of Direct and Strong Products of Graphs

The frequency assignment problem is to assign a frequency which is a nonnegative integer to each radio transmitter so that interfering transmitters are assigned frequencies whose separation is not in a set of disallowed separations. This frequency assignment problem can be modelled with vertex labelings of graphs. An $L(2,1)$-labeling of a graph $G$ is a function $f$ from the vertex set $V(G)$ to the set of all nonnegative integers such that $vert f(x)-f(y)vertgeq 2$ if $d(x,y)=1$ and $vert f(x)-f(y)vertgeq 1$ if $d(x,y)=2$ , where $d(x,y)$ denotes the distance between $x$ and $y$ in $G$. The $L(2,1)$ -labeling number $lambda(G)$ of $G$ is the smallest number $k$ such that $G$ has an $L(2,1)$-labeling with $max{f(v):vin V(G)}=k$. This paper considers the graph formed by the direct product and the strong product of two graphs and gets better bounds than those of KlavŽar and Špacapan with refined approaches.      

A 0.1–5 GHz Cryogenic SiGe MMIC LNA

In this letter, the design and measurement of the first SiGe integrated-circuit LNA specifically designed for operation at cryogenic temperatures is presented. At room temperature, the circuit provides greater than 25.8 dB of gain with an average noise temperature $(T_{e})$ of 76 K $(NF=1 {rm dB})$ and $S_{11}$ of $-$ 9 dB for frequencies in the 0.1–5 GHz band. At 15 K, the amplifier has greater than 29.6 dB of gain with an average $T_{e}$ of 4.3 K and $S_{11}$ of $-$14.6 dB for frequencies in the 0.1–5 GHz range. To the authors' knowledge, this is the lowest noise ever reported for a silicon integrated circuit operating in the low microwave range and the first matched wideband cryogenic integrated circuit LNA that covers frequencies as low as 0.1 GHz.      

A $Q$ -Band Four-Element Phased-Array Front-End Receiver With Integrated Wilkinson Power Combiners in 0.18-$mu{{hbox{m}}}$ SiGe BiCMOS Technology

A four-element phased-array front-end receiver based on 4-bit RF phase shifters is demonstrated in a standard 0.18- $mu{{hbox{m}}}$ SiGe BiCMOS technology for $Q$-band (30–50 GHz) satellite communications and radar applications. The phased-array receiver uses a corporate-feed approach with on-chip Wilkinson power combiners, and shows a power gain of 10.4 dB with an ${rm IIP}_{3}$ of $-$13.8 dBm per element at 38.5 GHz and a 3-dB gain bandwidth of 32.8–44 GHz. The rms gain and phase errors are $leq$1.2 dB and $leq {hbox{8.7}}^{circ}$ for all 4-bit phase states at 30–50 GHz. The beamformer also results in $leq$ 0.4 dB of rms gain mismatch and $leq {hbox{2}}^{circ}$ of rms phase mismatch between the four channels. The channel-to-channel isolation is better than $-$35 dB at 30–50 GHz. The chip consumes 118 mA from a 5-V supply voltage and overall chip size is ${hbox{1.4}}times {hbox{1.7}} {{hbox{mm}}}^{2}$ including all pads and CMOS control electronics.      

Development of Thin-Film Liquid-Crystal-Polymer Surface-Mount Packages for $Ka$ -Band Applications

In this paper, we present the design and development of thin-film liquid-crystal-polymer (LCP) surface-mount packages for $Ka$ -band applications. The packages are constructed using multilayer LCP films and are surface mounted on a printed circuit board (PCB). Our experimental results demonstrate that the package feed-through transition including a PCB launch and bond wires achieve a return loss of better than $-$20 dB and an insertion loss of less than 0.4 dB around $Ka$ -band. We achieve a measured port-to-port isolation of the package to be more than 45 dB across the $Ka$-band. We demonstrate the package feed-through circuit model by comparing the simulation of model and bare die measurement data to a packaged amplifier measurement. Finally, we report an LCP cavity that has a measured fine leak rate of ${hbox{3.6}}times {hbox{10}}^{-8} {hbox{atm}}cdot{hbox{cc/s}}$ .      

Electrical Properties of $hbox{Bi}_{5}hbox{Nb}_{3} hbox{O}_{15}$ Thin Film Grown on $hbox{TiN}/hbox{SiO}_{2}/ hbox{Si}$ at Room Temperature for Metal–Insulator–Metal Capacitors

Buckling was observed in $hbox{Bi}_{5}hbox{Nb}_{3}hbox{O}_{15}$ (BiNbO) films grown on $hbox{TiN}/hbox{SiO}_{2}/hbox{Si}$ at 300 $^{circ}hbox{C}$ but not in films grown at room temperature and annealed at 350 $^{circ}hbox{C}$. The 45-nm-thick films showed a high capacitance density and a low dissipation factor of 8.81 $hbox{fF}/muhbox{m}^{2}$ and 0.97% at 100 kHz, respectively, with a low leakage current density of 3.46 $hbox{nA}/hbox{cm}^{2}$ at 2 V. The quadratic and linear voltage coefficients of capacitance of this film were 846 $hbox{ppm}/hbox{V}^{2}$ and 137 ppm/V, respectively, with a low temperature coefficient of capacitance of 226 $hbox{ppm}/^{circ}hbox{C}$ at 100 kHz. This suggests that a BiNbO film grown on a $hbox{TiN}/ hbox{SiO}_{2}/hbox{Si}$ substrate is a good candidate material for high-performance metal–insulator–metal capacitors.      

A Short Range, Low Data Rate, 7.2 GHz-7.7 GHz FM-UWB Receiver Front-End

A 9 mW FM-UWB receiver front-end for low data rate ( $≪$$ hbox{50~kbps}$), short range ( $≪$$hbox{10~m}$) applications operating in the ultra-wideband (UWB) band centered at 7.45 GHz is described in this paper. A single-ended-to-differential preamplifier with 30 dB voltage gain, a 1 GHz bandwidth FM demodulator, and a combined (preamp/demodulator) receiver front-end were fabricated in 0.25 $muhbox{m}$ SiGe:C BiCMOS and characterized. Measured receiver sensitivity is $-hbox{85.8~dBm}$ while consuming 9 mW from a 1.8 V supply, and $-hbox{83~dBm}$ consuming 6 mW at 1.5 V. 15-20 m range line-of-sight in an indoor environment is realized, justifying FM-UWB as a robust radio technology for short range, low data rate applications. Multi-user and interference capabilities are also evaluated.      

A 0.5-V Wideband Amplifier for a 1-MHz CT Complex Delta-Sigma Modulator

This brief presents a fully differential wideband amplifier for 0.5-V supply. The amplifier employs a gate-input two-stage topology and a dc common-mode feedback circuit with a Miller-amplified capacitor for frequency compensation. Designed in a 130-nm triple-well complementary metal–oxide–semiconductor process with regular $V_{T}$ transistors, the amplifier achieves a simulated performance of 51-dB dc open-loop gain, 112-MHz unity gain bandwidth, and 67 $^{ circ}$ phase margin with a load of 6.5 pF/19.6 $hbox{k}Omega$ , and consumes 600 $muhbox{W}$ at 0.5-V supply. The proposed amplifier is incorporated in a continuous-time complex Delta-Sigma modulator with a 1-MHz signal bandwidth and 64$times$ oversampling ratio. In the simulations, the modulator achieves a 72.5-dB signal-to-noise-plus-distortion ratio and consumes 2.3 mW at 0.5 V.      

Design of a Beam Switching/Steering Butler Matrix for Phased Array System

A compact broadband 8-way Butler matrix integrated with tunable phase shifters is proposed to provide full beam switching/steering capability. The newly designed multilayer stripline Butler matrix exhibits an average insertion loss of 1.1 dB with amplitude variation less than $pm$2.2 dB and an average phase imbalance of less than 20.7$^{circ}$ from 1.6 GHz to 2.8 GHz. The circuit size is only $160times 100 {rm mm}^{2}$, which corresponds to an 85% size reduction compared with a comparable conventional microstrip 8-way Butler matrix. The stripline tunable phase shifter is designed based on the asymmetric reflection-type configuration, where a Chebyshev matching network is utilized to convert the port impedance from 50 $Omega$ to 25 $Omega$ so that a phase tuning range in excess of 120$^{circ}$ can be obtained from 1.6 GHz to 2.8 GHz. To demonstrate the beam switching/steering functionality, the proposed tunable Butler matrix is applied to a 1 $times$ 8 antenna array system. The measured radiation patterns show that the beam can be fully steered within a spatial range of 108 $^{circ}$.