This paper aims to study the design of a low-power single-balanced mixer for downconversion in wireless RF receivers. The proposed circuit is designed to work at a radiofrequency of 1.9GHz using CMOS 0.18 µm technology. The obtained results show a conversion gain equal to 7 dB and low power consumption of 3.86mW at 1.8.V supply voltage. The single side band noise figure performance was founded to be 8.dB. These results show a good potential of this CMOS mixer and justify its use for low-power wireless communications. ...

The aim of this paper is to study the miniature patch antenna (patch antenna λ/8) fed by a coaxial line, and the design comparison of this antenna by two methods: The Transmission Line Model (TLM) and the G-L-C Parallel Circuit Model. An adaptation of the microstrip antenna λ/8, by the setting up of a capacitor in the middle of the probe-feed is achieved.

The modeling and the design of the miniature patch antenna will be made by the TLM; a particular attention will be carried on the results got on the level of the bandwidth. The second part is based on the idea of microstrip patch antenna starting from the G-L-C Parallel Circuit Model, (by order of 14 %), which gives the bandwidth more interest than in the first method (TLM).

The results obtained by the two methods (Input Impedance, reflection coefficient, SWR and bandwidth) will be given by the programs in MATLAB software.

...

The rectangular patch antenna is set to play a significant role in the development of the next-generation wireless communication systems. The purpose of this report is to provide the design of the rectangular patch antenna system by studying the performance of patch antenna array, and to achieve the electronic scanning in space of the radiation patterns by a four rectangular patch antennas plan array. The designed patch antenna square array will have an array of four elements and its performance will be evaluated in terms of radiation patterns.Results given by the MATLAB and PCAAD (Personal Computer Aided Antenna Design) software will be tabulated and antenna radiation patterns will be plotted for discussion before wrapping up with a conclusion and suggestion on future developments. ...

A linear array is a simple configuration and commonly used, however it is essential to investigate its performances.There are four basic factors that influence on performances of an array patches antennas: spacing between patches, number of patches in the array, amplitude distribution, and excitation phase, all these parameters will be varied to find the optimal configuration.This paper is consecrated to the variation of the excitation phase, and the other factors are fixed, what is going to permit us to scanning the radiation pattern of a linear array of four rectangular patches microstrip antennas in the E-plane and in the H-plane, without resorting to a mechanical displacement of this array [1]. The effect on the direction of the main beam of those arrays (linear and planar) will be studied. We are going to compare our theory used and programmed in MATLAB by one simulations executed in the PCAAD (Personal Computer Aided Antennas Design) software [2].However, we are going to explore the radiation pattern by the variation of the excitation phase of patches of a square array for four rectangular microstrip patches antennas array, as we takes the same elements of the previous linear array[3], [4], and we are going to put them under shape of a planar square array. ...