Many circuits in broadband applications require the coupling of RF signals, which can be a complicated process since it involves removing the DC component to allow only the high-frequency AC component to pass or bypass. Removing the AC component from a DC line is done by placing a coupling capacitor in series with the path the signal takes.
Before small cell technology took its place as a central component to realizing the promise of 5G networks, it played an important role in helping to improve the coverage and capacity of 4G. These mini base stations could be installed in discrete locations like on buildings or streetlights and became part of heterogeneous networks—together with traditional macro base stations—to improve service in high-traffic locations such as sporting events and concert venues. In this pursuit, small cells have proven valuable for extending signal penetration and increasing wireless density and these small, lightweight devices will continue to be a key technology for the data-intensive transition to 5G.
As with everything in 2020, the International Microwave Symposium (IMS) is a bit different this year. We’re gearing up for the live stream event next week, Aug. 4-6, where we’ll participate in the virtual exhibition and give six online MicroApp technical presentations.
In general, a capacitor assembly attaches multiple capacitors together into a single subassembly. This approach results in increased electrical performance such as higher voltages, higher capacitance, or higher power, while also simplifying manufacturing assembly and providing a significant reduction in board space needed.
The Wilkinson Power Divider, designed by Ernest Wilkinson in the 1960s, uses quarter wave transformers to split an input signal into two equal phase output signals. Since the design is reciprocal, Wilkinson Power Dividers can also be used as a power combiner. With this flexibility, they are widely used in many RF and microwave communication systems, including those with multiple channels or complex feed networks.
Topics: RF and Microwave
As a fundamental component of circuit design, equivalent series resistance (ESR) is the measurement of all the non-ideal electrical resistances in series with a capacitor. When current flows through a multilayer ceramic capacitor (MLCC) due to application of alternating voltage, heat is generated in the MLCC due to the losses, specifically ESR. As a result, this self-heating can cause various performance and reliability issues in the circuits of today’s more complex and smaller electronic systems.
DC link capacitors are commonly used in power converters as an intermediary buffer between an input source to an output load that have different instantaneous power, voltages, and frequencies. In electric vehicle (EV) applications, DC link capacitors help offset the effects of inductance in inverters, motor controllers, and battery systems. They also serve as filters that protect EV subsystems from voltage spikes, surges, and electromagnetic interference (EMI).
Recently, Microwave Journal editors Pat Hindle and Gary Lerude sat down with Knowles Precision Devices product line manager Tim Brauner to discuss how our innovative high-performance components are helping RF engineers improve the size, weight, and performance (SWaP) of mmWave designs.
To meet consumer demand for longer driving ranges and faster charging, electric vehicle (EV) manufacturers are redesigning vehicles to move from 400V to 800V battery systems. As a result of using higher operating voltages, EV designers and original equipment manufacturers (OEMs) need components, such as multi-layer ceramic capacitors (MLCCs), that can withstand voltages well beyond those expected under normal operating conditions. For example, a drivetrain running off an 800V battery system may be subjected to a withstand test of up to 4kV DC for 60 seconds, which is a standard safety test in high voltage systems.
As the demand for more network capacity, improved network performance, and more reliable coverage are all growing, operating in the mmWave spectrum is becoming an increasing more attractive option. To address this demand, the use of 28-GHz small cells, which are compact, lightweight devices mounted on outdoor equipment such as lampposts or telephone poles, is becoming a practical and affordable way to deploy 5G in the mmWave spectrum.