This expanded and thoroughly revised edition of Thomas H. Lee's acclaimed guide to the design of gigahertz RF integrated circuits features a completely new chapter on the principles of wireless systems. The chapters on low-noise amplifiers, oscillators and phase noise have been significantly expanded as well. The chapter on architectures now contains several examples of complete chip designs that bring together all the various theoretical and practical elements involved in producing a prototype chip. First Edition Hb (1998): 0-521-63061-4 First Edition Pb (1998); 0-521-63922-0

The Design of CMOS Radio-Frequency Integrated Circuits: RF CIRCUITS THROUGH THE AGES

The performance of additive manufactured (AM) RF circuits and antennas is continuously improving, and in some cases these AM components are comparable to state-of-the-art circuits made with traditional manufacturing techniques. Medium to high-power waveguides made with AM methods such as copper-plated plastics, selective laser melting (SLM), and copper additive manufacturing (3-D CAM) have shown good performance up to terahertz frequencies. In this paper, binder jetting (BJ) metal printing is characterized using electron beam microscopy [scanning electron microscopy (SEM)] and energy dispersive spectroscopy. The RF performance of the 3-D-printed circuits is benchmarked with Ka-band cavity resonators, waveguide sections, and a filter. An unloaded resonator $Q$ of 616 is achieved, and the average attenuation of the WR-28 waveguide section is 4.3 dB/m. The BJ technology is tested with a meshed parabolic reflector antenna, where the illuminating horn, waveguide feed, and a filter are printed in a single piece. The antenna shows a peak gain of 24.56 dBi at 35 GHz.

Ka-Band Characterization of Binder Jetting for 3-D Printing of Metallic Rectangular Waveguide Circuits and Antennas

Three-dimensional (3D) printing technology is an area of research that has received great attention in the last decade and it is pointed out by many as the future of manufacturing. 3D printing can be described as an additive process that creates a physical object from a digital model, depositing materials layer by layer. The ability to quickly produce complex structures at a reduced cost and without wasting materials is the main reason why this additive manufacturing technique is increasingly being used instead of conventional manufacturing processes. 3D printing has been applied in several scenarios, including automotive, maritime and construction industry, healthcare, as well as in the antenna research field. This paper reviews the current state-of-the-art of 3D printed antennas. Firstly, an overview of 3D printing technology is presented and then a vast number of 3D printed antennas, categorized by their construction process, are described. Finally, the main advantages and some of the limitations of using 3D printing technology in the construction of Radio Frequency (RF) structures are presented.

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Antenna Design Using Modern Additive Manufacturing Technology: A Review

The 3D printing technology is catching attention nowadays. It has certain advantages over the traditional fabrication processes. We give a chronical review of the 3D printing technology from the time it was invented. This technology has also been used to fabricate millimeter-wave (mmWave) and terahertz (THz) passive devices. Though promising results have been demonstrated, the challenge lies in the fabrication tolerance improvement such as dimensional tolerance and surface roughness. We propose the design methodology of high order device to circumvent the dimensional tolerance and suggest specific modelling of the surface roughness of 3D printed devices. It is believed that, with the improvement of the 3D printing technology and related subjects in material science and mechanical engineering, the 3D printing technology will become mainstream for mmWave and THz passive device fabrication.

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Review of 3D Printed Millimeter-Wave and Terahertz Passive Devices

While RFID technology is gaining increased attention from industrial community deploying different RFID-based applications, it still suffers from reading collisions. As such, many proposals were made by the scientific community to try and alleviate that issue using different techniques either centralized or distributed, monochannel or multichannels, TDMA or CSMA. However, the wide range of solutions and their diversity make it hard to have a clear and fair overview of the different works. This paper surveys the most relevant and recent known state-of-the-art anti-collision for RFID protocols. It provides a classification and performance evaluation taking into consideration different criteria as well as a guide to choose the best protocol for given applications depending on their constraints or requirements but also in regard to their deployment environments.

/pdf/a-survey-of-rfid-readers-anticollision-protocols-zhuptrhpit.pdf

A Survey of RFID Readers Anticollision Protocols

Microdispensing of thick-film conductive paste has been demonstrated as a viable approach for manufacturing microwave planar transmission lines. However, the performance and upper frequency range of these lines is limited by the cross-sectional shape and electrical conductivity of the printed paste, as well as the achievable minimum feature size which is typically around $100~\mu \text{m}$ . In this paper, a picosecond Nd:YAG laser is used to machine slots in a 20–25- $\mu \text{m}$ -thick layer of silver paste (Dupont CB028) that is microdispensed on a Rogers RT5870 substrate, producing coplanar waveguide (CPW) transmission lines with 16– $20~\mu \text{m}$ -wide slots. It is shown that the laser solidifies an about 2- $\mu \text{m}$ -wide region of the edges of the slots, thus significantly increasing the effective conductivity of the film and improving the attenuation constant of the lines. The extracted attenuation constant at 20 GHz for laser machined CB028 is 0.74 dB/cm. CPW resonators and filters show that the effective conductivity is in the range from 10 to 30 MS/m, which represents a $100\times $ improvement when compared to the values obtained with the exclusive use of microdispensing. This paper demonstrates that a hybrid approach of additive manufacturing and laser machining enables the fabrication of higher frequency circuits (up to at least 40 GHz) with improved performance.

Characterization and Modeling of K-Band Coplanar Waveguides Digitally Manufactured Using Pulsed Picosecond Laser Machining of Thick-Film Conductive Paste

Radio frequency identification (RFID) tag design is generally focused specifically on either off-metal or on-metal configurations. In this letter, passive 2-D and 3-D RFID tags are presented, which perform similarly in both configurations. The tags operate in the industrial, scientific, and medical (ISM) RFID UHF bands (864–868 MHz and 902–928 MHz). A matching loop consisting of two parallel stubs to ground is used for impedance matching to a passive integrated circuit, which has −18-dBm sensitivity. A planar 2-D tag with a footprint of 13126.5 mm2 is first introduced, showing a simulated gain of approximately 3 dBi and a measured read range of 10 m (for 31-dBm transmit power from the reader) in both on-metal and off-metal conditions. The tag is miniaturized into a 3-D geometry with a footprint of 2524.25 mm2 (520% reduction) and achieves the same broadside simulated on-metal gain. The antennas are fabricated using a 3-D printed acrylonitrile butadiene styrene. The conductive layer is realized by microdispensing silver paste (Dupont CB028). A meshed ground configuration is explored in order to accomplish a 50% conductive paste reduction without disrupting the performance. The proposed tags are compared to commercially available tags as well as previously published tags in terms of read range and size. The tags in this letter present an improvement in terms of read range, gain, and area with respect to previous designs covering the ISM RFID UHF bands. Moreover, the performance of these tags is maintained in on- and off-metal conditions, achieving comparable performance and a reduction in volume of 11 482% with respect to the best tag reported.

UHF RFID Tags for On-/Off-Metal Applications Fabricated Using Additive Manufacturing

In this paper a 3D tag antenna geometry is proposed for UHF RFID systems. Two antennas were built over different dielectric materials with similar properties using both Direct Digital Manufacturing and traditional photolithography and copper etching. The impedance matching between the antenna arms and the passive RFID integrated circuit was accomplished with the H-slot matching technique with a simulated 10 dB return loss bandwidth that allows the tag to operate in the American and European ISM RFID bands of 902–928 MHz and 864–868 MHz, respectively. The antennas were compared to commercially available tags in size, weight and read distance, showing a read range improvement of 136% (for a threshold power of 30 dBm) with respect to the best tag tested. A reduction in length of 78 % with respect to a planar 2D model was also achieved. The radiation patterns were measured, showing an omni-directional beam pattern.

3D tag with improved read range for UHF RFID applications using Additive Manufacturing

The performance of additively manufactured microwave passive elements and interconnects continues to improve as better materials, and process techniques are developed. In this paper, laser-enhanced direct print additive manufacturing (LE-DPAM) is used to fabricate capacitors and inductors for coplanar waveguide (CPW) circuits. Acrylonitrile butadiene styrene is used as the dielectric that is printed using fused deposition modeling, and DuPont CB028 conductive paste is deposited using microdispensing. These two techniques are combined with picosecond-pulsed laser machining to achieve $\simeq 12$ - $\mu \text{m}$ slots on printed conductors, producing aspect ratios greater than 2:1. The same laser is used to fabricate vertical interconnections that allow for the fabrication of multilayer inductors. Inductances in the range of 0.4–3 nH are achieved, with a maximum quality factor of 21, selfresonance frequencies up to 88 GHz, and an inductance per unit of area of 5.3 nH/mm2. Interdigital capacitors in the range of 0.05–0.5 pF are fabricated, having a maximum quality factor of 1000, a capacitance per unit area of 1 pF/mm2, and selfresonances up to 120 GHz. All the components are made on the center line of a CPW that is 836- $\mu \text{m}$ wide. The results show that LE-DPAM enables the fabrication of compact passive circuits that can be easily interconnected with MMIC dies, which at the same time can be manufactured as part of a larger component. This enables the fabrication of structural electronics that are functional into the millimeter-wave frequency range. Bounds on the inductances and capacitances per unit area are related to material and geometry limitations.

Laser-Assisted Additive Manufacturing of mm-Wave Lumped Passive Elements

The effect of a low permittivity cladding used in a multilayer end-fire dielectric rod antenna (DRA) design is studied in terms of return loss, gain, and half-power beamwidth (HPBW) in the extended Ku band (10–18 GHz). Gain improvement ranging from 4 to 7 dB, when compared to a single-layer design of the same length, is achieved using cladding permittivities between 1.6 and 2.6. For example, a cladding of ϵr = 1.6 leads to a peak gain increment of 4.5 dB at 18 GHz and a 20° HPBW reduction compared to the noncladded rod. It is also demonstrated that this design has the same maximum gain as a noncladded design that is 1.8 times longer. The cladding permittivity in the multilayer DRA can be adjusted to achieve peak performance at different frequencies within the band, while providing gain enhancement in the entire band without reducing the bandwidth.

Ramiro A. Ramirez

Papers

Characterization and Modeling of K-Band Coplanar Waveguides Digitally Manufactured Using Pulsed Picosecond Laser Machining of Thick-Film Conductive Paste

UHF RFID Tags for On-/Off-Metal Applications Fabricated Using Additive Manufacturing

3D tag with improved read range for UHF RFID applications using Additive Manufacturing

Laser-Assisted Additive Manufacturing of mm-Wave Lumped Passive Elements

Multilayer Dielectric End-Fire Antenna With Enhanced Gain