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A new phased-array feeding network that results in low sidelobe levels (SLLs) over a limited scan region is demonstrated. The proposed concept groups the individual phased-array elements into random sequences of nonuniform subarrays and employs a single phase shifter (PS) for each subarray. When these random sequences are optimized, the resulting phased array can scan over a wide angle with low SLLs. A methodology for analyzing the random arrays is provided, multiple cases with different numbers of PSs and subarray groups are optimized, and design guidelines are presented. The performance of the random arrays is compared with conventional uniform subarrays and it is shown that random arrays reduce the number of PSs by up to 40% while preserving the same performance. A random array is demonstrated at 7.9 GHz for a 30-element linear design (scan in one direction) with 12 PSs and results in a half-power beamwidth of 4.1° with a scan angle up to ±14° and SLLs less than −15 dB. It is also shown that random arrays can be used in 2-D phased arrays with up to 60% reduction in the number of PSs. Application areas are in low-cost phased arrays with limited scan angles such as automotive radars or landing systems. [ABSTRACT FROM PUBLISHER]

A 10-GHz outphasing modulator is implemented in a 45-nm CMOS silicon-on-insulator process. The modulator is designed to provide high linearity and can operate at high data rates by using 256-QAM while maintaining low error vector magnitude (EVM). Four high-speed 10-bit digital-to-analog converters (DACs) are integrated with dual in-phase and quadrature upconverters. To deliver high output power to an off-chip power amplifier, stacked field-effect transistor current buffers are used to isolate the modulator from the load and mitigate device breakdown. As a result, this modulator delivers 23 dBm to a differential 100-\Omega load. The high-resolution DACs provide a fine control of the phase between the outphased signals and support more than 60 dB of dynamic range and power steps smaller than 1 dB over the entire output power range. The outphasing modulator demonstrates an EVM of 2.2% at 80 Mbit/s and an EVM of 3.4% at 1.1 Gbit/s for 256-QAM. To our knowledge, this is the first demonstration of an outphasing modulator operating above 1 Gb/s. [ABSTRACT FROM PUBLISHER]

A novel approach to beam steering is presented using an array composed of elements each supporting a unique radiating mode. The one-dimensional (1-D) beam synthesis properties of the novel ideal multiple mode dipole array are quantified using Fourier synthesis and shown to have significant improvement in scan range compared to a conventional linear dipole reference array. A hybrid phased array composed of multiple mode subarrays is also proposed and shown to be an efficient tradeoff between performance improvement and design complexity. Reasonable agreement is obtained between the simulated and measured impedance and radiation pattern properties of a four-element multiple mode array. Finally, a 16-element hybrid phased array composed of four four-element multiple mode subarrays is fabricated and measured. The array is shown to have a 3-dB scan range of \pm 68^\circ, which is in good agreement with the simulated value of \pm 69^\circ at the design frequency of 4.6 GHz. Additionally, the 3-dB bandwidth of the array is more than 1 GHz at broadside. This bandwidth reduces to approximately 300 MHz at the widest scan angles, which is consistent with an equivalent conventional linear array. [ABSTRACT FROM PUBLISHER]

This paper presents a novel tunable dual-band bandstop filter based on doubly tuned RF transformers. This design results in two distinct notch frequencies in a single resonator using silicon varactor diodes. The 2-pole tunable dual-band bandstop filters are implemented using printed circuit board (PCB) transformers and air-coil transformers. With PCB transformers, the lower frequency can be tuned at 513–845 MHz while the higher frequency can be tuned at 715–1151 MHz with a \notch level > 16~\dB. With air-coil transformers, a single-band 2-pole notch filter with wide rejection bandwidth is achieved. The design results in 604–982 MHz tuning with a 20-dB rejection bandwidth of 27–45 MHz. Also, by implementing a series varactor in a transformer, the separation between two coupled frequencies can be changed. The topology can be easily extended to higher order filters and design equations are presented. [ABSTRACT FROM PUBLISHER]

A high power-handling radio frequency (RF) microelectromechanical systems capacitive switch with low sensitivity to both in-plane stress and stress gradients is presented. The novel switch consists of four cantilever beams, which are tied together using an optimized center joint to minimize the effects of biaxial stress and stress gradients. Dimples with a thickness of 0.3 $\mu $ m are used to result in an air dielectric in the down-state position, which greatly improves the reliability, while still maintaining a measured capacitance ratio of 5. The switch is capable of handling an RF power >12$ W under hot switching conditions, as well as having low sensitivity to temperature variations ( \sim 20$ mV/°C for ). Application areas are in high power reconfigurable filters, matching networks, and tunable antennas for modern communication systems. [2014-0092] [ABSTRACT FROM AUTHOR]

This article presents a wideband scalable 17.7–20.2-GHz 1024-element $K$ -band satellite communication (SATCOM) receive (Rx) phased array with reconfigurable polarization. The phased array uses silicon Rx beamformer (BF) chips and silicon low-noise amplifiers (LNAs) and is able to receive either linear, rotated linear, circular clockwise, or anticlockwise polarization. It demonstrates a measured 3.47° half-power beamwidth (HPBW), more than 25-dB cross-polar discrimination (XPD), and +8.1-dB/K gain-to-noise (G/T) per polarization, and has more than 80-dB Tx-band isolation. The phased array is able to scan to ±70° in all planes without grating lobes and $\cos ^{1-1.2}(\theta)$ scan loss. The array aperture measures 22.4 cm $\times22.4$ cm. To our knowledge, this is the largest single printed circuit board (PCB) SATCOM $K$ -band phased-array receiver to date with the highest G/T and represents the highest level of integration at millimeter waves. [ABSTRACT FROM AUTHOR]

This work presents a 15–57 GHz multiband/ multistandard phased-array architecture for the fifth-generation (5G) new radio (NR) frequency range 2 (FR2) bands. An eight-element phased-array receive module is demonstrated based on two four-channel wideband beamformer chips designed in the SiGe BiCMOS process and flipped on a low-cost printed circuit board. The SiGe Rx chip employs RF beamforming and is designed to interface to a wideband differential Vivaldi antenna array. Each channel consists of a low-noise amplifier (LNA), active phase shifter with 5-bit resolution, variable gain amplifier (VGA), and differential-to-single-ended stage. The four channels are combined using a wideband two-stage on-chip Wilkinson network. The beamformer has a peak electronic gain of 24–25 dB and a 4.7–6.2 dB noise figure (NF) with a −29 to −24 dBm input $P_{\boldsymbol {1\,dB}}$ at 20–40 GHz. The eight-element phased-array module also achieved ultra-wideband frequency response with flat gain and low-system NF. The phased array scans ±55° with $ < -12$ -dB sidelobes demonstrating multiband operation. A 1.2-m over-the-air (OTA) link measurement using the eight-element Rx module supports 400-MHz 256-QAM OFDMA modulation with < 2.76% error vector magnitude (EVM) at multiple 5G NR FR2 bands. To the author’s knowledge, this work achieves the widest bandwidth phased array enabling the construction of multistandard systems. [ABSTRACT FROM AUTHOR]

This article presents a wideband scalable 27–31-GHz 1024-element $Ka$ -band SATCOM transmit (TX) phased array with embedded RF drivers and reconfigurable polarization. The phased array uses silicon TX beamformer (BF) chips and printed stacked-patch antennas on an FR-4 based printed circuit board (PCB) to TX either linear, rotated linear, circular clockwise, or anticlockwise polarization. It demonstrates a measured 3.5° half-power beamwidth (HPBW), 35-dB cross-polar discrimination (XPD), sub-1-dB axial ratio (AR), +49.5-dBW peak effective isotropic radiated power (EIRP) on axis, and the ability to scan to ±70° in all planes without grating lobes and $cos^{1-1.1}(\theta)$ scan loss. The measured error vector magnitude (EVM) of less than 2.3% and the adjacent channel power ratio (ACPR) of less than −32 dBc across all scans at $P_{1\,\text{dB}}$ make it suitable as a compact high-efficiency SATCOM transmitter. The array aperture measures 14.9 cm $\times14.9$ cm, and it is scalable to larger phased arrays with 4096 and a higher number of elements. To the best of our knowledge, this represents the highest level of integration at millimeter waves and with the highest measured EIRP from a SATCOM phased array. [ABSTRACT FROM AUTHOR]

This article presents a 1024-element Ku-band phased-array transmitter for mobile satellite communications. The array is based on eight-channel transmit (TX) SiGe beamformer chips. Dual-polarized stacked-patch antennas enable the array to synthesize linear, rotated-linear, and left- and right-hand circular polarization. The array consists of four quadrants of 256-element subarrays, each of which has 64 beamformer chips and a driver chip assembled on a printed circuit board (PCB). The array achieves an effective isotropic radiated power (EIRP) of 75 dBm per polarization (78-dBm circular polarization) and scans to ±75° in all planes. This is achieved using an antenna spacing of $\lambda $ /2 at 14.4 GHz in an equilateral triangular grid. The array also results in 30-dB cross-polarization rejection up to 60° scan angles. Measured error vector magnitude (EVM) for 50-, 100-, 200-, and 500-MBd QPSK and 8 phase-shift keying (8PSK) waveforms results in at most 1.5%rms and 2.5%rms at $P_{1\textrm {dB}}$ and $P_{\mathrm{ sat}}$ , respectively, at 14 GHz over all scan angles. Also, the adjacent channel power ratio (ACPR) was measured as −32 dB for 200- and 500-MBd QPSK and 8 phase-shift keying (8PSK) waveforms at $P_{1\textrm {dB}}$ at 14 GHz. To the authors’ knowledge, this work presents a state-of-the-art planar phased-array system with high EIRP for Ku-band satellite communication (SATCOM) mobile transmitter terminals. [ABSTRACT FROM AUTHOR]

This article presents a 1024-element dual-polarized Ku-band (10.7–12.7 GHz) satellite communication (SATCOM) receive (RX) phased array. The array consists of four 16 $\times16$ subarray tiles, each of which comprises 64 eight-channel beamformer chips, 256 dual-channel low-noise amplifiers (LNAs), and 256 dual-polarized antennas built on an affordable printed circuit board (PCB). The antennas spaced at $\lambda $ /2 spacing at 12.2 GHz in an equilateral triangular grid allow scanning up to x±70° in all planes while maintaining a cross-polarization level $ < -30$ dB. The use of LNAs just after the antennas enables a low-noise operation with an antenna gain-to-noise temperature (G/T) of 10.5 dB/K ($T_{\mathrm {ant}} =20$ K) at broadside while maintaining a directivity of 34 dB at 11.7 GHz. Also, a two-pole/two-zero filter is placed between the LNA and the beamformer chip to greatly attenuate any transmit leakage signal at 14–14.5 GHz. The lightweight, low-cost PCB with all silicon chips and a thickness of 3.4 mm presents a viable candidate for Ku-band SATCOM ground and Satcom-On-The-Move (SOTM) terminals. [ABSTRACT FROM AUTHOR]

This article presents an ultralow-profile and lightweight Ku-band transmit phased array with 256 dual-polarized antenna elements for SATCOM on-the-move (SOTM) terminals. The antennas are placed in a square grid with λ/2 spacing at 14 GHz. At normal incidence, the phased array results in a measured effective isotropic radiated power (EIRP) of 64.5 and 66.5 dBm at P1~dB and Psat, respectively, per polarization. The measured patterns, in E- and H-planes, show almost ideal patterns with a wide scanning range of ±60°, a 3-dB instantaneous bandwidth of 13.0–14.6 GHz, and a cross-polarization isolation of 27 dB up to ±45° and 23 dB at ±60° scan angles. In the circular polarization mode, the measured axial ratio (AR) is <1.1 dB at 14–14.5 GHz. The phased array is also capable of synthesizing deep nulls (−30 to −40 dB) over a wide range of angles, thereby reducing unintended radiation to geostationary orbit (GEO) satellites. Transmit noise analysis is presented and shows that the array signal-to-noise ratio (SNR) is dominated by the block upconverter (BUC) and not by the beamformers. An error vector magnitude (EVM) of 2.8%–3.5% was achieved over a wide scan range for QPSK, 8-PSK, and 16-PSK waveforms with 100-MHz bandwidth. The array near-ideal performance, compact size, low profile with 3.5-mm thickness, and ultralightweight of 212 g make it ideal for affordable Ku-band SATCOM terminals. [ABSTRACT FROM AUTHOR]

This article presents a Ku-band phased-array receive tile with 256 elements. The design is based on 64 dual-polarized beamformer chips assembled on a printed circuit board (PCB) with dual-polarized antennas and an integrated Wilkinson combiner network and can operate at any polarization (linear, rotated-linear, and circular). The 256 elements are spaced 0.52λ apart at 12.7 GHz in the x- and y-directions. The measured patterns show near ideal patterns with a wide beam scanning range of ±70° (V- and H-pol) and a high cross-polarization rejection of 27 dB. The array has a 3-dB instantaneous scanning bandwidth of 10.6–12.5 GHz. In circular polarization mode, the measured axial ratio (AR) is 0.5 dB at 11.75 GHz for both left- and right-hand circular polarizations. The tile design is scalable to allow large-scale phased-array construction with 1024 elements or higher. Extensive measurements are presented, showing the versatility of this approach. Also, the dual-polarization feeds can be optimized to result in very low cross-polarization for circular and slanted-linear polarizations at all scan angles. The array performance, compact size, ultralightweight of 258 g, and low profile with 3.5-mm thickness make it suitable for affordable mobile Ku-band SATCOM on the move (SOTM) terminals. [ABSTRACT FROM AUTHOR]

This article presents a low-power, high-gain, high-linearity phased-array transmit (Tx) beamformer chip in a 45-nm RFSOI process. An architecture employing a power amplifier with neutralization, a 180° active phase shifter and 11/22/45/90° passive phase shifter result in high linearity and low power consumption. The measured gain is 22 dB with a 3-dB bandwidth of 57.5–65.5 GHz and an ${\mathrm{ OP}}_{1\,{\mathrm{ dB}}}$ and ${\mathrm{ OP}}_{\mathrm{ sat}}$ of 7.5–10 dBm and 9.5–11.5 dBm at 57–64 GHz, respectively. A peak power-added efficiency (PAE) of 14.6% and 17.6% at 60 GHz is achieved at $P_{1\,{\mathrm{ dB}}}$ and $P_{\mathrm{ sat}}$ , respectively. The measured rms phase and gain errors are $ < 4^{\circ }$ and < 0.7 dB at 57–64 GHz, respectively. The beamformer chip also has 14-dB gain control with less than 2.8 dB drop in the ${\mathrm{ OP}}_{1\,{\mathrm{ dB}}}$. Complex modulation measurements using a 400 MBaud 64-QAM waveform show an error vector magnitude (EVM) of 5% (−26 dB) at an average power of 5 dBm and with a dc power consumption of only 52 mW, resulting in a linear PAE of 6.1%. Also, 18–20 Gbps data rates are demonstrated with an EVM < 5% (64-QAM) and < 9% (16-QAM) at 60 GHz. To the author’s knowledge, this work achieves state-of-the-art linearity and efficiency for 60-GHz communication systems. [ABSTRACT FROM AUTHOR]

This article presents a 23.5–29.5-GHz $8\times 8$ phased array for wideband multistandard applications. The array is based on wideband high-performance $2\times 2$ transmit/receive (TRX) quad-beamformer chips with 6 bit of phase control and 8 bit of gain control. The antenna is designed using a stacked-patch structure combined with a two-stage impedance matching network to enhance its bandwidth. The $8\times 8$ phased array achieves an effective isotropic radiated power (EIRP) of 54.8 dBm at P1dB with a 3-dB bandwidth of 23.5–30.5 GHz and can scan to ±60° in the azimuth plane and +/40° in the elevation plane with excellent patterns with a single-point calibration at 27 GHz. Measured error vector magnitude (EVM) for a 64-QAM 200 and 800-Mbaud waveforms result in a system EVM of 5% (−26 dB) in the TX mode at an average EIRP of 46–47 dBm at 24.5–29.5 GHz. Also, the wideband array is capable of 16-QAM 24-Gb/s links with an EVM <16% over all scan angles. An interband carrier aggregation (CA) system is also demonstrated with the wideband array using 200-Mbaud 64-QAM waveforms with 25- and 29-GHz carriers. The phased-array phase and amplitude settings are chosen such that the 25- and 29-GHz waveforms are radiating simultaneously at the same angle with low scan loss, resulting in an efficient system. Also, the out-of-band third-order intermodulation products generated by the power amplifier on each element are filtered out by the antenna. CA measurements with up to 50° scan angles are demonstrated with low EVM. To the best of our knowledge, this is the first demonstration of CA in millimeter-wave fifth-generation (5G) systems. [ABSTRACT FROM AUTHOR]

This article presents a 5G 37–42-GHz $8\times 8$ phased array. The array is based on $2\times 2$ SiGe transmit/receive (TRX) beamformer chips in the SiGe technology with 6 bits of phase control and 8 bits of gain control. A detailed study is presented, showing the effects of array-level amplitude and phase errors on the radiated error vector magnitude (EVM) of 64-element arrays. The array scans to ±60° in the azimuth plane and ±50° in the elevation plane with low sidelobes. The measured peak effective isotropic radiated power (EIRP) is 51 dBm at Psat with a 3-dB bandwidth of 36–41.5 GHz. A 39-GHz communication system is also demonstrated along with a high-pass filter and an integrated upconverter/downconverter and achieves a local oscillator (LO) and image rejection level of 50 dBc, meeting FCC requirements of <−13 dBm/MHz of total leakage power. The array achieves < 5% EVM (−26 dB) using a 64-QAM 200-MHz waveform at an average EIRP of 44 dBm over all scan angles, including the LO and upconverter/downconverter contributions. A 30-Gb/s communication link with 64-QAM modulation is also shown. To our knowledge, this is the first demonstration of a 39-GHz phased-array communication system for 5G applications. [ABSTRACT FROM AUTHOR]

This article presents 60-GHz $2\times 64$ - and $2 \times 256$ -element dual-polarized dual-beam wafer-scale phased-array transceivers with integrated up/downconverters. The $2\times 64$ -element phased array is built as a single reticle and occupies $21\times21$ mm2. It is based on RF beamforming transmit/receive (TRX) channels with 5-bit phase and 9-bit gain control, dual nested 1:64 distribution networks with Wilkinson divider/combiners, line amplifiers (LAs), and dual up/downconverters with a shared local-oscillator (LO) multiplier chain. The differential on-chip antenna feeds are electromagnetically (EM) coupled to a high-efficiency quartz superstrate dipole antenna array placed $\lambda $ /2 apart in the horizontal and vertical directions. Four $2\times 64$ -element phased-array reticles are then bondwire-stitched in the intermediate-frequency (IF)/LO domain to form a $2\times 256$ -element phased-array super-reticle that occupies $42\times42$ mm2. The $2\times 64$ - and $2\times 256$ -element phased arrays scan to ±50° in the elevation ($E$ -plane) and azimuth ($H$ -plane) planes. The equivalent isotropically radiated power (EIRP) of the $2\times 64$ -element array is 37–38 dBm with a 3-dB bandwidth of 60–64 GHz, while that of the $2\times 256$ -element array is 42–44 dBm with a 3-dB bandwidth of 61–63 GHz per polarization. A communication link using the $2\times 64$ -element array is demonstrated with quadrature phase-shift keying (QPSK), 16-quadrature amplitude modulation (QAM), and 64-QAM waveforms, reaching 12–16-Gb/s data rates per polarization at 1.3 m. To the best of our knowledge, this article presents the first fully polarimetric scalable wafer-scale phased-array transceivers using simple reticle-to-reticle stitching, resulting in the state-of-the-art functionality and complexity on a single chip. [ABSTRACT FROM AUTHOR]

This article presents a packaged SiGe BiCMOS reflectometer for 0.01–26-GHz two-port vector network analyzers (VNAs). The reflectometer chip is composed of a resistive bridge coupler and two wideband heterodyne receivers for coherent magnitude and phase detection. In addition, a high-linearity receiver channel is designed to accommodate ~20 dBm of RF input power to the reflectometer. External sources are used to provide stimulus over the entire bandwidth, and a high-linearity shunt 50- $\Omega $ switch is placed at the input of each reflectometer chip to provide a matched condition for better measurement accuracy. The measured dynamic range (DR) of the heterodyne receiver is 129±3 dB at 0.01–26 GHz at an IF resolution bandwidth (RBW) of 10 Hz. The reflectometer chip is packaged on a low-cost printed circuit board (PCB) and connectorized for repeatable measurements. Several passive and active device-under-test (DUTs), such as filters and amplifiers, are measured in single- and dual-port complex $S$ -parameter setup at 0.01–26 GHz. The single-chip reflectometer results in excellent agreement with commercially available test equipment and with minimal magnitude and phase difference. Several definitions (mean deviation and error vector) are used to quantify the measurement accuracy. A measured $S_{21}$ of −80 dB is obtained using high-rejection filters. An in-depth DR analysis of possible limiting factors in the measurement setup is also presented. This article shows that silicon-based highly integrated reflectometers can be used in low-cost VNAs with excellent DR and accuracy. [ABSTRACT FROM AUTHOR]

This paper presents two tunable three-feed triple-band antennas using series or shunt tuning devices. The paper includes a theoretical analysis in the effects of the series and shunt tuning devices on antenna size and performance. Each antenna has three feeds to cover three bands within the long-term evolution (LTE) frequency range (0.7–2.7 GHz). Each antenna operating frequency is independently tunable by a varactor diode (series or shunt). The antennas are well matched at all feeds (S 11 -S 33 < −10 dB) and the isolation between the feeds is < −20 dB in most cases. The antenna volume is 66 × 100 × 3.15 mm3 and is placed on RO4003C ( ε r = 3.55) printed-circuit board (PCB). Radiation patterns and antenna efficiency are measured inside a Satimo chamber and the results agree well with the simulations. This paper shows the first comparison between series and shunt tuning devices on small antennas. Application areas include cellular communications, carrier aggregation, and advanced multiband systems. [ABSTRACT FROM AUTHOR]

This paper presents a 64-element 28-GHz phased-array transceiver for 5G communications based on $2\times 2$ transmit/ receive (TRX) beamformer chips. Sixteen of the $2\times 2$ TRX chips are assembled on a 12-layer printed circuit board (PCB) together with a Wilkinson combiner/divider network and 28–32-GHz stacked-patch antennas. The 64-element array results in 1.1 dB and 8.9° rms amplitude and phase error, respectively, with no calibration due to the symmetric design of the $2\times 2$ beamformer chips and the PCB Wilkinson network. The effect of phase and amplitude mismatch between the 64 elements is analyzed and shown to have little impact on the 64-element array performance due to the averaging effects of phased arrays. Detailed pattern, effective isotropic radiated power (EIRP), and link measurements performed without any array calibration are presented and show the robustness of the symmetrical design technique. The phased array can scan to ±50° in azimuth ($H$ -plane) and ±25° in elevation ($E$ -plane) with low sidelobes and achieves a saturated EIRP of 52 dBm with 4-GHz 3-dB bandwidth. A 300-m wireless link is demonstrated with a record-setting data rate of 8–12 Gb/s over all scan angles using two 64-element TRX arrays and 16-/64-QAM waveforms. [ABSTRACT FROM AUTHOR]

This paper presents 60-GHz wafer-scale transmit phased arrays with 64- and 256-elements spaced $\lambda $ /2 apart in the $x$ - and $y$ -directions, and occupying an area of 21.4 $\times $ 22 mm2 (471 mm2) and 41.4 $\times $ 42 mm2 (1740 mm2), respectively. The 64-element phased array is built as a complete reticle and includes 64 independent transmit channels with 5-b phase control, 3-b (9 dB) amplitude control, a saturated output power of 3 dBm at the antenna port, a 1–64 distribution network with redundant line amplifiers, and a high-efficiency on-chip antenna at each element. In addition, redundant serial digital interface and power strips, dual series metal–insulator–metal capacitors, and multiple RF inputs are employed for improved yield. The 256-element array uses the same phased-array blocks as the 64-element design, but is built using a subreticle stitching technique so as to result in a chip which is larger than the standard reticle size (22 $\times $ 22 mm2). The 64- and 256-element arrays result in a half-power beamwidth of 12° and 6° in the $E$ - and $H$ -planes, a directivity of 23 and 29 dB, respectively, and scan to ±55° in the $E$ - and $H$ -planes with near-ideal patterns and a cross-polarization level of lesser than −30 dB. The measured equivalent isotropically radiated power (EIRP) of the 64-element array is 38 dBm at 62 GHz with a 3-dB bandwidth of 61–63 GHz, while that of the 256-element array is 45 dBm at 61 GHz with a 3-dB beamwidth of 58–64 GHz. A 1–4-Gb/s communication system is also demonstrated using the 64-element phased array up to ±45° scan angles, and at 4-, 30-, and 100-m ranges. To the best of our knowledge, this paper represents the first demonstration of large size (64- and 256-element) phased-array transmitters on a single wafer. [ABSTRACT FROM PUBLISHER]

This paper reports the generation, amplification, and radiation of modulated signals at 45 GHz using a single-chip CMOS power amplifier coupled to a 2\, \times \,2 antenna array. Using digital predistortion, complex constellations were demonstrated for wide modulation bandwidth, which allows high data rates to be transmitted in a spectrally efficient manner. After predistortion, a 98-MS/s 1024-QAM signal with peak-to-average power ratio of 7 dB was demodulated with an error vector magnitude of 1.3%. The measured equivalent isotropically radiated power was 26.2 dBm. The corresponding average RF power produced by the CMOS chip, considering a simulated antenna gain of 12 dB, was 14.2 dBm. [ABSTRACT FROM PUBLISHER]

This paper presents extremely compact single-pole multiple-throw radio frequency (RF) microelectromechanical system switches, SP7T and SP11T, based on a symmetric circular switch topology. The switch dimensions are 0.61~mm\times 0.61 mm, which is smaller than typical CMOS Si-on-insulator switches. The SP7T and SP11T switches, which are insensitive to stress gradient effects, achieve simulated contact and restoring forces of 0.3–0.4 mN (per a switch) at 90–100 V. The SP7T and SP11T switches also achieve isolation levels of 50–19 dB and 50–17 dB, respectively, and insertion loss of 0.3–1.2 dB and 0.3–1.7 dB, respectively, at 0.1–10 GHz. The measured on-resistance is 4.5–2.5 $\Omega $ at 75–100 V, respectively, in an open environment and limited by contact contamination. The measured switching time is 7–10 \mu $ s. Cold-switched reliability tests of SP7T and SP11T switches show greater than 10^{8} Hz with an RF power of 0.1–1 W, which is sufficient power handling capability for 3G and 4G systems. [2014-0001] [ABSTRACT FROM AUTHOR]