1. Summary Microwave indoor propagation offers a good opportunity for object positioning. The use of the pulse radar method for measuring distances and angles are quite unsuitable for indoor applications. The resolution of this method is too low and there is a minimal distance requirement of the pulse radar measurement that is usually higher than the room size. In this paper the phase method of...

This paper outlines the basic theory of a development of the Gilbert mixer. The bipolar junction transistor (BJT) differential pair widely used as the RF input stage is replaced by a bisymmetric Class-AB topology based on translinear principles. It does not have inherent gain compression, affording a greatly extended signal capacity. The linearity of variants of the basic form is excellent, pro...

Three-dimensional (3D) microwave imaging reflectometry has been developed in the large helical device to visualize fluctuating reflection surface which is caused by the density fluctuations. The plasma is illuminated by the probe wave with four frequencies, which correspond to four radial positions. The imaging optics makes the image of cut-off surface onto the 2D (7 × 7 channels) horn antenna ...

In rapid-scan EPR the magnetic field or frequency is repeatedly scanned through the spectrum at rates that are much faster than in conventional continuous wave EPR. The signal is directly-detected with a mixer at the source frequency. Rapid-scan EPR is particularly advantageous when the scan rate through resonance is fast relative to electron spin relaxation rates. In such scans, there may be o...

Excellent progress in the development of Submillimeter-wave SIS and HEBmixers has been demonstrated in recent years. At frequencies below 800 GHz these mixers are typically implemented using waveguide techniques, while above 800 GHz quasi-optical (open structure) methods are often used. The choice of waveguide offers several advantages over quasi-optical techniques, such as the use of broadband...

In order to make precise measurements of laser frequencies in the infrared region, it is generally necessary to run a laser cw at a low power level. This is done to insure frequency stability that is very hard to obtain in high-power, Q-switched lasers. Microwave techniques such as heterodyning can be used for extremely accurate measurements of absolute laser frequencies, provided a radiation d...

Radio astronomy requires SIS mixers and receivers with very high stability. The goal for the total power stability of the ALMA receivers is 1x10 over 1 second. The SIS mixer is one of the most critical components in the receiver signal chain determining stability. Most changes in mixer noise and gain are due to variations of its operating conditions. In this paper we present accurate measuremen...

Frequency translation which converts the original signal to a much lower baseband frequency signal is a vital role in the RF receiver design. In this work, a high linear down-conversion Gilbert cell mixer at 100MHz is designed using TSMC 0.18μm RF CMOS process. Linearity is an important performance measure in RF circuits particularly in mixer design. In this paper, the two types of linearizatio...

9 The effect of mixer shear strain rate on the performance of a model 10 micro-crystalline cellulose pharmaceutical paste undergoing extru11 sion–spheronisation was studied using a laboratory scale planetary 12 mixer and a screw-based mixer. The maximum shear strain rate in 13 each mixer was estimated. Five pastes were prepared, one each at 14 97 and 265 s−1 in the planetary mixer, and one each...