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Generation and Photonic Processing of Radio Waves, Tera-Waves and Multi-Carrier Lightwaves
Published in Le Nguyen Binh, Photonic Signal Processing, 2019
The traditional approach toward RW signal processing is that an RW signal originated at an RF (Radio Frequency) source, or came from an antenna, is fed to an RF circuit that performs the signal processing tasks either at the RF signal level or at an IF (intermediate frequency) band after a down-conversion operation. In any case, the RF circuit is capable of performing the signal processing tasks for which it has been designed only within a specified (often reduced) spectral band. However, this approach results in poor flexibility since changing the band of the signals to be processed requires the design of a novel RF circuit and the use of different hardware technologies. Furthermore, even if the RF carrier is not changed, the nature of the modulating signal might require more bandwidth or sampling speed from the processor. These drawbacks are often termed in the literature as the electronic bottleneck.1,2,3,4 Also, the emerging Tera-Hz EM waves would require the signal processing functions performed in the photonic domain.
Wireless Building Blocks Using SiGe HBTs
Published in John D. Cressler, Circuits and Applications Using Silicon Heterostructure Devices, 2018
Radio-frequency (RF) circuit design using silicon technologies has progressed over the past decade from small-scale building blocks to complete systems-on-a-chip enabling applications such as 3G wireless telephony [1]. The hundreds of active and passive components used in a handset in the mid-1990s were reduced to a single silicon chip and a handful of passives (filters, capacitors, etc.) by 2000 [2,3]. This was achieved through improvements in the technology, smaller passive components (small and lighter filter packages), and innovations in circuit design and radio architecture. It can be argued that the current success of wireless technology as a consumer product with mass-market appeal has been made possible by the cost, size, and performance advantages of integration on silicon. The performance improvements offered by silicon–germanium heterostructure bipolar transistors (SiGe HBTs) in BiCMOS technologies are enabling even further advances in wireless transceiver performance and integration. The first section of this chapter reviews the aspects of RF circuit design relevant to the design of wireless building blocks. Low-noise amplifier (LNA), mixer, and voltage-controlled oscillator (VCO) circuits are then examined in detail.
Force-System Resultants and Equilibrium
Published in Richard C. Dorf, The Engineering Handbook, 2018
All over the world, wireless communications services have enjoyed phenomenal growth over the past two decades. It was only in late 1983 that the first commercial cellular telephone system in the U.S. Was deployed by Ameritech in the Chicago area. This was the analog service called Advanced Mobile Telephone System (AMPS). Today, cellular telephone services, most of them digital, are available throughout the world, and are beginning to rival fixed-line telephone services both in terms of availability and number of users. In a span of less than 20 years, the number of mobile wireless subscribers worldwide has grown from zero to over a billion users. This remarkable growth demonstrates not only the strong desire of people around the world to communicate to one another while on the move, but also the tremendous strides that technology has made in both fulfilling and further fueling this need. While the ability to communicate using radio signals was demonstrated by Marconi more than a century ago, it was the remarkable developments during the past few decades in RF circuit fabrication, digital signal processing, and several miniaturization technologies that made it possible to deploy and deliver wireless communication services at the scale and scope that we see today.
A novel double-π model for multilayer inductor based on 130 nm SiGe process and modified parameter extraction procedure
Published in Electromagnetics, 2019
Xiuping Li, Cheng Cao, Yajing Hou, Jiangfan Liu, Zhe Wang, Qing Xia, Hua Zhu
The potential large consumer markets have attracted a great deal of interest among radio-frequency integrated circuit (RFIC) designers in the past few years. Integrated spiral inductor is a critical passive component in a variety of IC designs such as 60-GHz low-noise amplifiers (LNAs) (Jang and Nguyen 2016; Yu et al. 2017), power amplifiers (PAs) (Wu, Lin, and Hsiao et al. 2018; Xia, Fang, and Boumaiza 2018), voltage-controlled oscillators (VCOs) (Chang, Chiang, and Yang 2015; Jin, Wu, and Xue 2018). Equivalent circuit model for on-chip inductor is necessary to predict the inductance characteristics and is of significance for radio-frequency (RF) circuit designs.
Adaptive segmentation-based evaluation of material properties of dielectric sheets using microwave NDE
Published in Nondestructive Testing and Evaluation, 2023
Shankar Aenagandula, Subrata Mukherjee, Neeraj Rao, Yiming Deng
Microwave material property measurement plays a crucial role in various applications such as composite materials characterisation, RF circuit design, materials production, radome inspection, aircraft manufacturing, concrete structure inspection, and agricultural goods [1–13]. Compared to other non-destructive evaluation (NDE) methods like ultrasound, eddy current, and X-ray, microwave measurement offers advantages such as low cost, excellent penetration in non-metallic materials, low power requirements, high resolution, and numerous other benefits as mentioned in [14–16].
Design of Tri-Band Microstrip Patch Rectenna for Radio Frequency Energy Harvesting System
Published in IETE Journal of Research, 2022
Manavalan Saravanan, Anumuthu Priya
Table 1 gives an overall performance comparison of the proposed rectenna with other traditional rectenna. It observed that the antenna is designed on a single-layer substrate and hence very much feasible to integrate with other RF circuit components. Further, the antenna operates at three frequency bands has better efficiency characteristics in the operating bands when compared to other conventional antennas.