A broadband LNA and mixer for digital video broadcasting applications using a 0.18‐μm CMOS process

Abstract

generates R and D patterns of two received signals. Antenna array and coupler were integrated and R-D patterns obtained, in vertical and horizontal directions, by constructing two separate same design circuits: one for finding DOA for h 1 and other circuit finding DOA for h 2 . By putting R-D patterns in Eq. (3), AOA has been estimated. This task first has been simulated in ADS layout and optimized for expected results. Later, simulated designs of both circuits were fabricated on RT Duroid 5880 substrate. Each circuit's 3D R-D patterns were taken as measured data. Experimentally obtained data was imported in Matlab for analysis of DOA. Measured S-parameters and far field R-D patterns are very close to simulated results. From R-D patterns of each circuit, DOA has been estimated for both axis. Both circuits are able to find direction of received signal from 0 to 6408 in their respective axis. For performance measurement, rms error also has been calculated which is less than 58 in both circuits. However, it increases more as we go above the 408 which suggests that designed DOA system works well for 0 to 6408. By looking at all simulated and measured results, proposed system design of DOA works in satisfactory range which in result fulfills the purpose of this article.ABSTRACT: In this study, a broadband low noise amplifier (LNA)/ mixer for digital video broadcasting-satellite receiver tuner was fabricated by a 0.18-mm complementary metal oxide semiconductor (CMOS) process. The proposed broadband LNA receives positive feedback and incorporates a single-ended differential converter to mixer. Two attenuators are used to obtain good noise performance and high linearity. Moreover, the designed CMOS LNA/mixer achieved gain controls in 3-dB steps, an input second-order intercept of 1.37 dBm, and an input third-order intercept of 23.6 dBm in high-gain low-frequency mode. The 6.4-dB noise of LNA was achieved in the frequency range of 950-2150 MHz. The circuit consumes a total current of 25 mA at a supply voltage of 1.8 V and the chip area of the LNA and the mixer are 0.8 3 0.53 mm 2 and 0.8 3 0.6 mm 2 , respectively.