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This paper presents a new form of gap waveguide technology -- the half-height-pin gap waveguide. {The gap waveguide technology is a new transmission line technology introduced recently, which makes use of the stopband of wave propagation created by a pair of parallel plates, one PEC (perfect electric conductor) and one PMC (perfect magnetic conductor), with an air gap in between less than a quarter of the wavelength at operation frequency. Applying this PEC/PMC gap plate structure to ridged waveguides, rectangular hollow waveguides and microstrip lines, we can have the ridged gap waveguides, groove gap waveguides and inverted gap waveguide microstrip lines, respectively, without requiring a conductive or galvanic contact between the upper PEC and the lower PMC plates. This contactless property of the gap waveguide technology relaxes significantly the manufacturing requirements for devices and antennas at millimeter wave frequencies. PMC material does not exist in nature, and an artificial PMC boundary can be made by such as periodic pin array with the pin length about a quarter wavelength. However, the quarter-wavelength pins, referred to as the full-height pins, are often too long for manufacturing. In order to overcome this difficulty, a new half-height-pin gap waveguide is introduced.} The working principles and Q factors for the half-height-pin gap waveguides are described, analyzed and verified with measurements in this paper. {It is concluded that half-height-pin gap waveguides have similar Q factors and operation bandwidth to the full-height-pin gap waveguides.} As an example of the applications, a high gain planar array antenna at V band by using the half-height-pin gap waveguide {has been designed and} is presented in the paper {with a good reflection coefficient and high aperture efficiency}.

A wideband microstrip planar radial 1:19 power divider is developed in this study. The power divider design is simple with conventional impedance-transformation method, and a single substrate is employed, thereby reducing the cost for the antenna. To verify our design, the power divider was fabricated and tested. It can be observed that it achieves an impedance bandwidth of 29.4% (1.98 GHz-2.67 GHz) (VSWR 2), the transmitted magnitude and phase imbalance for 19 outputs are ± 0.1 dB and ± 1 deg, respectively. The power divider is also integrated into the 19-element circularly polarized (CP) antenna array as the feed network; the simulated results show that the power divider can apply appropriate amplitudes and phases for the antenna array to obtain the good CP performance.

This paper presents the design and implementation of Ka band broadband hybrid integrated image rejection mixer with a fourth harmonic mixer as unit mixer. Detailed design and analysis have been carried out. The mixer was fabricated by hybrid microwave integrated circuit (HMIC) process based on the thin film ceramic substrate which can reduce the cost compared to monolithic microwave integrated circuit (MMIC). The measured results showed conversion loss less than 11.2 dB and image rejection ratio (IRR) more than 20 dB in 4 GHz RF bandwidth. It can also play the role of up-converter from the test data.

Background After the publication of the CONSORT 2010 statement, few studies have been conducted to assess the reporting quality of randomized clinical trials (RCTs) on treatment of diabetes mellitus with Traditional Chinese Medicine (TCM) published in Chinese journals. Objective To investigate the current situation of the reporting quality of RCTs in leading medical journals in China with the CONSORT 2010 statement as criteria. Methods The China National Knowledge Infrastructure (CNKI) electronic database was searched for RCTs on the treatment of diabetes mellitus with TCM published in the Journal of Traditional Chinese Medicine, Chinese Journal of Integrated Traditional & Western Medicine, and the China Journal of Chinese Materia Medica from January to December 2011. We excluded trials reported as “animal studies”, “in vitro studies”, “case studies”, or “systematic reviews”. The CONSORT checklist was applied by two independent raters to evaluate the reporting quality of all eligible trials after discussing and comprehending the items thoroughly. Each item in the checklist was graded as either “yes” or “no” depending on whether it had been reported by the authors. Results We identified 27 RCTs. According to the 37 items in the CONSORT checklist, the average reporting percentage was 45.0%, in which the average reporting percentage for the “title and abstract”, the “introduction”, the “methods”, the “results”, the “discussion” and the “other information” was 33.3%, 88.9%, 36.4%, 54.4%, 71.6% and 14.8%, respectively. In the Journal of Traditional Chinese Medicine, Chinese Journal of Integrated Traditional & Western Medicine, and the China Journal of Chinese Materia Medica the average reporting percentage was 42.2%, 56.8%, and 46.0%, respectively. Conclusions The reporting quality of RCTs in these three journals was insufficient to allow readers to assess the validity of the trials. We recommend that editors require authors to use the CONSORT statement when reporting their trial results as a condition of publication.

A kind of circularly polarized microstrip antenna is designed in S band. The Wilkinson power divider integrated with the microstrip 90 deg phase shifter is used each unit and the patch is coupled by two orthogonal H-shaped, which can enhance the isolation of the two ports and improve the circularly polarized performance. The antenna array gain is about 14 dB. The axial-ratio value within 3dB from −20 deg to 20 deg. The cross-polarization levels in zenith direction are better than −23 dB. This results indicate that the proposed antenna realizes a good circularly polarization performance.

This paper presents a novel compact power divider with third harmonic suppression and also can provide a direct current (dc) path which could simplify the other active circuits, such as power amplifier, in the complicated phase array antenna feeding network area. The proposed power divider achieves 20% size reduction compared to the conventional Wilkinson power divider and it is beneficial to the miniaturisation of the phased array antenna. From the measured results, it can be seen that the simulated results can instruct the practical circuit very well.

A miniaturized three-way Wilkinson power divider that provides equal power split over a wide bandwidth implemented on a single-layer printed circuit board (PCB) is presented. In this work, the bent microstrip line replaces the straight microstrip line of the conventional power divider, thus, the size of the proposed power divider is 44.75 mm times 70 mm, which is much smaller than the conventional proposed power divider. Good experimental performances of the proposed power divider, including an even power split, low loss, and good isolation between the output ports are obtained. Measured results show that VSWR of the input and three output ports is less than 1.6 across the bandwidth from 0.7 to 1.1 GHz.

Background Due to language limitations, little is known about the reporting quality of randomized clinical trials (RCTs) on the treatment of coronary heart disease (CHD) with traditional Chinese medicine (TCM) in Chinese Journal of Integrated Traditional and Western Medicine (CJITWM). Objective In this study, we utilized the CONSORT 2010 statement to understand the reporting quality of RCTs on CHD with TCM from the CJITWM. Methods The China National Knowledge Infrastructure (CNKI) electronic database was searched for CJITWM RCTs on the treatment of CHD with TCM, published between Janurary 1, 2006 and December 31, 2011. We excluded articles reported as “animal studies,” “topic review,” “diagnostic test,” “editorials,” or “others.” The CONSORT checklist was applied to evaluate the reporting quality of all eligible articles by two independent authors after extensive discussion. Each item was graded as either “yes” or “no” depending on whether the authors had reported it or not. Results We identified 21 articles meeting our inclusion criteria. The percentage of 11 of the 37 items was 4.8~95.2%, 14 of the 37 items were reported in all included articles, while 12 items were not mentioned at all. The average reporting percentage for the “title and abstract” section was 52.4%, for the “introduction” section 100.0%, for the “methods” section 45.4%, for the “results” section 57.1%, for the “discussion” section 79.4%, and for the “other information” section 17.5%. Conclusion In general, the reviewed RCTs were not consistent with the CONSORT 2010 statement. Authors should adhere to the CONSORT statement in reporting RCTs; editorial departments may consider the CONSORT statement as a guideline and should instruct authors to write manuscripts, and reviewers to judge them according to CONSORT statutes.