A near field scanning is usually time-consuming to map the electromagnetic field along the surface of a device. In this paper, a dual probe is proposed with a U-shaped loop to sense radio-frequency (RF) magnetic and electric fields simultaneously, so that the one-time scanning by the dual probe can replace the two-time scanning by single detector probes. Different from the traditional near field scanning by using a single detector probe and spectrum analyzer, the proposed scanning can be achieved by the two-output probe and a two-port vector network analyzer connecting to the probe. The efficient near field scanning measurements of the electric and magnetic field on a conductorbacked coplanar waveguide transmission line and an RF power divider by using the dual probe are in agreement with those by using two single detector probes.

This paper presents a noncontact radio frequency voltage sensing of a printed trace by using a capacitive-coupled probe. The noncontact voltage sensing is demonstrated by using an open-end coaxial probe, and achieved through the transfer factor from the printed trace to the probe and a reconstruction algorithm. To validate the voltage sensing, known periodic and pulse voltages are injected into the printed trace and compared with the reconstructed waveforms. Our results demonstrate that the voltage sensing method can be used for measurement of a random waveform with period even down to 1 ns and single pulse with rise time down to 2 ns. In consideration of the flexible relocation of the probe, the voltage sensing accuracy caused by spatial errors is also investigated.

To measure the magnetic near field with high common mode noise rejection, a probe with the differential and symmetrical structure forming a detection loop is developed. Such measurement is performed by using a two-port vector network analyzer (VNA), and validated by using a microstrip line as device under test (DUT). In comparison to the measurement with traditional single-output magnetic near field probe, the electric field suppression of the proposed measurement can be improved by at least 10 dB in the frequency range of 3∼11 GHz, while the other characteristics basically remain unchanged.

In this letter, two novel broadband circularly polarized slot-microstrip antennas (SMPA) with circular and square structures are elaborated. The circular SMPA is composed of four crown patches as parasitic elements, four crown slots etched on a circular ground plane, and a circular loop sequential phase feeding structure. However, the square SMPA consists of four parasitic rectangular patches, four square slots with cut corners, and a square-loop feeding structure. In the circular SMPA, the parasitic crown patches and crown slots are used to excite multiple circularly polarized (CP) resonant modes, which are fed by a circular loop sequential phase feeding structure through capacitive coupling. Combined with these CP modes, the CP bandwidth of the presented antenna could be improved. Eventually, the proposed circular SMPA has a broad 3-dB axial ratio bandwidth (ARBW) of 20.6% (5.206.40, 5.8 GHz) and a wide 10-dB impedance bandwidth (IBW) of 25.8% (4.926.38, 5.65 GHz), which could occupy the WLAN (5.7255.85 GHz), ITS (5.8 GHz), and WIFI (5.85-5.925 GHz) bands.

In this paper, systematic characterization of the dual probe, which is designed for the near field simultaneous measurement of both electric and magnetic field, is investigated rgb0,0,0with a microstrip line as the device under test (DUT). The characterization includes frequency response, transmission performance, symmetry, reflection, the intrusion of probe to the DUT, isolation of electric and magnetic field responses, field profile and spatial resolution, and differential electric field suppression. The dual probes with different design are adopted to demonstrate the systematic characterization.

An extended model of through-silicon via (TSV)-based solenoid inductor is proposed to save on-chip areas for 3-D radio frequency (RF) ICs and package integration. To achieve a high inductance density, the nested topology consists of high-density TSVs in high-resistivity silicon substrate and multilayers of metals in compatible CMOS process. Then, an analytical inductance model, considering the mutual inductance of TSVs and complicated metal traces, is established and verified. The inductance variation in physical dimensions is studied based on the modeled and simulated results of a TSV solenoid inductor in single tier. The proposed TSV solenoid typology gets better performance at inductance density and quality factor around some frequencies through analytical model and full-wave simulations. Further studies are directed toward RF application overview according to broadband and low power consumption.