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The design and near-field characterization of an integrated rectenna on Globalfoundries 45-nm CMOS SOI technology are presented. The rectenna is intended for short range (below 8 cm) wireless powering and communication of integrated sensor systems and occupies an area of $700~\mu \text{m} \,\, \times 620~\mu \text{m}$ . Upon utilizing high (low)-resistivity Si substrate, the rectenna provides 1.2 (1.25) mW of dc power 1.1 (1.17) V rectified dc output voltage from a 0.95-GHz source with only 18 (30) dBm power feeding a horn antenna with 6-dB gain placed at a short distance (

A fully integrated broadband power amplifier (PA) is implemented in a standard 45-nm CMOS SOI technology. The PA is designed using a dynamically biased stacked SOI transistor approach, which constructively adds drain-source voltage signals of individual transistors while keeping their gate voltages within source and drain voltage limits. The design overcomes both low gate-oxide breakdown and low source-drain reach through voltages of nanoscale CMOS transistors. The number, size, and topology of transistors in the stack are optimized to deliver a relatively high linear output power over a wide range of frequencies. The amplifier under a supply voltage of 4.5 V measures a flat gain of 6 dB with -1-dB bandwidth of 6 to 26.5 GHz ( X-band to K-band). At 18 GHz, the PA under a supply voltage of 7.2 V measures a saturated output power (PSAT) of 26.1 dBm ( ~ 400 mW), a linear output power (P1 dB) of 22.5 dBm, and a peak power-added efficiency (PAE) of 11%. With a lower power supply voltage of 4.5 V, the PAE increases to more than 20% and stays above 17% with relatively constant PSAT and P1 dB for several measured frequencies in the range of 6 to 20 GHz. The PA occupies an active chip area of only 0.16 mm2.

A fully-integrated rectenna with a chip area of 0.43 mm2 is designed for ISM 915 MHz band for battery-less ultra-low-power body implantable applications. The circuit is implemented in GlobalFoundries 45 nm CMOS SOI technology and is based on a miniaturized slot antenna integrated with a novel full-wave cross-coupled bridge rectifier design that facilitates low turn-on voltage and very low leakage current. When excited by a 0.95 GHz signal through a horn antenna with an effective isotropic radiated power (EIRP) of 36 dBm, the rectenna provides more than 50 µW of DC power and a rectified DC voltage of higher than 1 V at distances below 16 cm. Power harvesting increases to 1.44 mW at distances below 2 cm. The device provides 1 V / 50 µW DC power when placed under a 1 cm thick chicken breast tissue at distances of up to 4 cm, while powered from 36 dBm EIRP transmitting antenna.

We present a high gain linearly polarized Ku-band planar array for mobile satellite TV reception. In contrast with previously presented three dimensional designs, the approach presented here results in a low profile planar array with a similar performance. The elevation scan is performed electronically, whereas the azimuth scan is done mechanically using an electric motor. The incident angle of the arriving satellite signal is generally large, varying between 25° to 65° depending on the location of the receiver, thereby creating a considerable off-axis scan loss. In order to alleviate this problem, and yet maintaining a planar design, the antenna array is designed to be consisting of subarrays with a fixed scanned beam at 45°. Therefore, the array of fixed-beam subarrays needs to be scanned ±20° around their peak beam, which results in a higher combined gain/directivity. The proposed antenna demonstrates the minimum measured gain of 23.1 dBi throughout the scan range (for 65° scan) with the peak gain of 26.5 dBi (for 32° scan) at 12 GHz while occupying a circular aperture of 26 cm in diameter.

A fully-integrated rectenna operating at around 1 GHz with a total chip area of 0.43 mm is implemented in Global Foundries 45 nm CMOS SOI technology. The design is based on a miniaturized slot antenna integrated with a novel full-wave cross-coupled bridge rectifier, with very low leakage current. When excited by a 1.1 GHz horn antenna with an effective isotropic radiated power (EIRP) of ∼ 30 dBm, the rectenna provides more than 50 μW of DC power and a rectified DC voltage of higher than 1 V at distances below 2 cm. Given the ample generated DC power, GHz operating frequency and small size of the circuit, this on-chip rectenna is suitable for miniaturized low-cost and battery-less implantable electronics and RFID tags.

The standard embossing process is limited to the fabrication of surface structures on relatively large polymer substrates. To overcome this limitation, a hybrid punching and embossing process was investigated for through-thickness embossing of three-dimensional parts. The embossing tool included a punching head and to-be- replicated features in the socket behind the punching head. The built-in punching head facilitated a through-thickness action and provided a closed-die environment for embossing pressure buildup. The method was used to emboss multichannel millimeter waveguides which requires uniform edges and accurate dimensions. With a tool temperature of 140°C, an embossing time of 3 min and a total cycle time of 7 min, discrete 4-channel waveguides were successfully embossed from a room-temperature ABS substrate. A computer model was established to study the flow behavior during through-thickness embossing. It was found that nonisothermal embossing conditions help confine the polymer in the cavity and reduce the outflow into the surrounding region, thus achieving complete fill of the cavity. POLYM. ENG. SCI., 47:2075–2084, 2007. © 2007 Society of Plastics Engineers

Importance Because of the similarity in clinical outcomes after elective open and endovascular repair of abdominal aortic aneurysm (AAA), cost may be an important factor in choosing a procedure. Objective To compare total and AAA-related use of health care services, costs, and cost-effectiveness between groups randomized to open or endovascular repair. Design, Setting, and Participants This unblinded randomized clinical trial enrolled 881 patients undergoing planned elective repair of AAA who were candidates for open and endovascular repair procedures. Patients were randomized from October 15, 2002, to April 15, 2008, at 42 Veterans Affairs medical centers. Follow-up was completed on October 15, 2011, and data were analyzed from April 15, 2013, to April 15, 2016, based on intention to treat. Main Outcomes and Measures Mean total and AAA-related health care cost per life-year and per quality-adjusted life-year (QALY). Results A total of 881 patients (876 men [99.4%]; 5 women [0.6%]; mean [SD] age, 70 [7.8] years) were included in the analysis. After a mean of 5.2 years of follow-up, mean life-years were 4.89 in the endovascular group and 4.84 in the open repair group ( P = .68), and mean QALYs were 3.72 in the endovascular group and 3.70 in the open repair group ( P = .82). Total mean health care costs did not differ significantly between the 2 groups (endovascular group, $142 745; open repair group, $153 533; difference, −$10 788; 95% CI, −$29 796 to $5825; P = .25). Costs related to AAA, including the initial repair, constituted nearly 40% of total costs and did not differ significantly between the 2 groups (endovascular group, $57 501; open repair group, $57 893; difference, −$393; 95% CI, −$12 071 to $7928; P = .94). Lower costs due to shorter hospitalization for initial endovascular repair were offset by increased costs from AAA-related secondary procedures and imaging studies. The probability of endovascular repair being less costly and more effective was 56.8% when effectiveness was measured in life-years and 55.4% when effectiveness was measured in QALYs for total costs and 31.3% and 34.3%, respectively, for AAA-related costs. Conclusions and Relevance In this multicenter randomized clinical trial with follow-up to 9 years, survival, quality of life, costs, and cost-effectiveness did not differ between elective open and endovascular repair of AAA. Trial Registration clinicaltrials.gov Identifier:NCT00094575

Millimeter-wave communication and radar systems have found numerous applications in recent years. These applications include millimeter-wave automotive collision avoidance radars, deep space communication and radar systems, w-band short range communication link, remote sensing of soil moisture and atmospheric monitoring in meteorological applications and climate sensing [1–4].

A fixed beam linearly polarized array for automotive satellite reception suitable for large scan angles has been demonstrated. Using the fixed beam subarray is the key to reduce the number of phase shifters at the cost of quantization errors and increased grating lobes. The azimuth beam steering is achieved mechanically utilizing an electronically controlled motor. The fixed beam array was successfully tested to receive actual satellite TV signals at locations where satellite view angle was close to 32deg.

A combined punching and embossing process was developed for fabrication of 3-D multichannel waveguides. The close-die setup overcomes the lateral flow problem experienced by the standard hot embossing process, thereby allowing buildup of embossing pressure and replication of 3-D features. The embossing tool for this purpose includes a punching head and the to-be-replicated features in the socket behind the punching head. During the process, the embossing tool first punches out a billet from a large blank and then embosses this billet in the socket. The combined operation allows for accurate blanking and provides a close-die process for embossing pressure buildup. ABS and PMMA were chosen as two polymers for waveguide embossing. In both cases, cycle times around 7 minutes resulted. While ejection problems were experienced by PMMA, a relatively brittle polymer, 4-channel waveguides with crispy edges and accurate dimensions were successfully fabricated using ABS, the tougher polymer.Copyright © 2007 by ASME

Objective Prior analysis in the Open vs Endovascular Repair Veterans Affairs (VA) Cooperative Study (CSP #498) demonstrated that survival, quality of life, and total health care costs are not significantly different between the open and endovascular methods of repair of abdominal aortic aneurysm. The device is a major cost of this method of repair, and the objective of this study was to evaluate the costs of the device, abdominal aortic aneurysm repair, and total health care costs when different endograft systems are selected for the endovascular repair (EVR). Within each selected system, EVR costs are compared with open repair costs. Methods The study randomized 881 patients to open (n = 437) or EVR (n = 444). Device selection was recorded before randomization; therefore, open repair controls were matched to each device cohort. Data were excluded for two low-volume devices, implanted in only 13 individuals, leaving 423 control and 431 endovascular patients: 166 Zenith (Cook Medical, Bloomington, Ind), 177 Excluder (W. L. Gore & Associates, Flagstaff, Ariz), and 88 AneuRx (Medtronic, Minneapolis, Minn). Mean device, hospitalization, and total health care costs from randomization to 2 years were compared. Health care utilization data were obtained from patients and national VA and Medicare data sources. VA costs were determined using methods previously developed by the VA Health Economics Resource Center. Non-VA costs were obtained from Medicare claims data and billing data from the patient's health care providers. Results Implant costs were 38% of initial hospitalization costs. Mean device (range, $13,600-$14,400), initial hospitalization (range, $34,800-$38,900), and total health care costs at 2 years in the endovascular (range, $72,400-$78,200) and open repair groups (range, $75,600-$82,100) were not significantly different among device systems. Differences between endovascular and corresponding open repair cohorts showed lower mean costs for EVR (range, $3200-$8300), but these were not statistically different. Conclusions The implant costs of endovascular aneurysm repair are substantial. When evaluating total health care system expenditures, there is large individual variability in costs, and there is no significant difference at 2 years among systems or when an individual system is compared with open repair.

The design aspects and the measured results of a novel miniaturized planar antenna are described. Such architectural antenna design is of great importance in mobile military communications where low visibility and high mobility are required. Slot radiating elements, having a planar geometry and capable of transmitting vertical polarization when placed nearly horizontal, are appropriate for the applications at hand. Slot antennas also have another useful property, so far as impedance matching is concerned. Basically, slot dipoles can easily be excited by a microstrip line and can be matched to arbitrary line impedances simply by moving the feed point along the slot. Antenna miniaturization can be achieved by using a high permittivity or permeability substrate and superstrate materials and/or using an appropriate antenna topology. We demonstrate miniaturization by designing an appropriate geometry for a resonant narrow slot antenna. A very efficient radiating element that occupies an area as small as 0.12/spl lambda//sub 0//spl times/0.12/spl lambda//sub 0/ is designed and tested. Simulation results, as well as the measured input impedance and radiation patterns of this antenna, are presented. This structure shows a measured gain of 0.5 dBi on FR4 substrate, which has a loss-tangent of the order of 0.01. Also, the effect of finite ground plane size on gain and resonant frequency is investigated experimentally.