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Unmanned Aircraft System Design
Published in R. Kurt Barnhart, Douglas M. Marshall, Eric J. Shappee, Introduction to Unmanned Aircraft Systems, 2021
Figure 9.5b shows the fractional cost breakdown of three representative high-performance UASs. In the case of the two larger UASs, the payload (sensor subsystem) is a more significant part of the total cost than on the sUAS. This reflects the trend that sUASs are more likely to be used to lower costs, but commercial-off-the-shelf (COTS) payloads (cameras, meteorological sensors, etc.) are not necessarily less capable. The larger airframes are generally designed for higher reliability and used to carry the more expensive, more power-demanding sensors for military and specialized civilian applications. Some of these sensors include electro-optical/infrared (EO/IR), light detection and ranging (LIDAR), synthetic aperture radar (SAR), and multifunction active electronically scanned array (AESA) radar sensors.
Adiabatic Concentration and Coherent Control in Nanoplasmonic Waveguides
Published in Sergey I Bozhevolnyi, Plasmonic, 2019
The idea of the spatio-temporal coherent control is analogous to that of the synthetic aperture radar (SAR) and conceptually similar active phased array radar (APAR), or active electronically scanned array (AESA) radar widely used in military and civilian radar systems. This idea can be introduced using a schematic shown in Fig. 15. An APAR consists of active oscillators that act as dipole antennas (shown by bold short vertical segments). Each of these antennas generates a pulse of radiation whose phase is controlled elctronically. If the phases are equal, as in Fig. 15(a), the beam produced by the interference of the waves emitted by each of the antennas is straight with the wavefront parallel to the array base. If there is a linear phase shift, as in panel (b), the beam is steered toward the emitters with retarded phases. For a parabolic-type modulation of the phases along the base line with a maximum phase delay in the center, a focused beam is formed as in panel (c). And finally, a linear combination of the linear and focusing phase shifts leads to the simultaneous steering and focusing as shown in Fig. 15(d). Due to the superposition principle, any superposition of the beams can be created by the correspondingly superimposing the phase modulations, provided that the number of the active antennas is large enough.
Simulators, Testbeds, and Prototypes of 5G Mobile Networking Architectures
Published in Mahmoud Elkhodr, Qusay F. Hassan, Seyed Shahrestani, Networks of the Future, 2017
Shahram Mollahasan, Alperen Eroğlu, Ömer Yamaç, Ertan Onur
Keysight Technologies has also introduced phased-array beamforming as a software module for SystemVue that can be used as a dynamic and accurate system-level simulator for analyzing active electronically scanned array (AESA) platforms, expanding range, reducing interference, and decreasing power consumption by enabling developers and architects to work on beamforming algorithms in 5G networks. By using this software, one can predict performance degradation of 5G networks in digital and hybrid beamforming architectures. By using AESA systems, architectures can access up to 256 elements in 5G applications. System developers can analyze the performance of baseband models that can reduce expenses and complexity thanks to the integration of SystemVue, MATLAB, and tools with RF and system design groups. This software is an add-on module for SystemVue and facilitates designers simply and quickly for simulating adaptive beamforming algorithms and multifunction arrays.
A millimetre-wave GaAs monolithic multifunctional quadrupler chip with high harmonic rejection and high output power flatness
Published in International Journal of Electronics Letters, 2022
Ce-Tian Wang, Hai-Feng Wu, Wei Tong, Yu-Nan Hua, Yi-Jun Chen, Liu-Lin Hu, Ji-Ping Lv, Qian Lin
A high harmonic rejection and high output power flatness Ka-band multifunctional quadrupler chip has been proposed. The design consideration and experimental results have been discussed. The chip performs a stable output power of 16.7 dBm at desired frequency range from 34 to 36 GHz. A conversion gain of 18 ± 0.8 dB is achieved at all working temperatures from ﹣55°C to +85°C. Unwanted fundamental, 2nd, 3rd and 5th harmonic in the output spectrum are suppressed by more than 50 dBc. The proposed MMIC can be effectively integrated into a multifunction module for wideband active electronically scanned array or phased array systems.