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Abstract A new 36.17 MHz all‐sky meteor radar was installed at McMurdo Station Antarctica (77.8°S, 166.7°E) in February 2018 to provide wind measurements in the mesosphere and lower thermosphere (MLT) region (70–120 km). This instrument is the highest latitude meteor radar currently in operation in the southern hemisphere; it joins two other meteor radars within the Antarctic Circle. The radar will provide long‐term continuous wind measurements of the polar region, and contribute to a greater understanding of MLT dynamics. This work describes the radar hardware and its context with other instruments in the region. The paper provides an overview of the spatial and temporal variation in meteor echoes over the observation period of March 2018 through October 2021. It also provides an analysis of the mean winds and solar tides over the first three years of operation; including a description of an observed 12 hr summertime wind oscillation consistent with previously documented observations of a westward propagating 12 hr non‐migrating tide of zonal wavenumber 1. 

Abstract We present a high‐fidelity measurement‐based nonlinear model of low‐complexity millimeter‐wave transmit and receive circuits for design and analysis of 1‐bit on‐off‐key (OOK) massive MIMO wireless communications systems. The receive model is based upon a fabricated 38 GHz energy detector, representative of state‐of‐the‐art OOK millimeter‐wave receivers. The model is validated with measurements and includes nonlinear noise modeling. Performance of a large‐scale massive MIMO system is predicted with the model, and predictions are compared against a 4‐transmit‐element, N‐receive‐element testbed. Finally, we compute the channel capacity of several OOK massive MIMO systems, exploring tradeoffs in power consumption and number of transmit and receive cells. Results indicate a 1‐bit OOK array with low power pre‐amplifiers can achieve similar capacity to a classical linear receiver with less than one tenth the power consumption. The 1‐bit array compensates for the per‐cell simplicity by increasing the total number of cells while maintaining low overall power consumption. 

Vanadium oxides are known for their metal–insulator transition (MIT), with V3O5 being notable for its transition temperature exceeding room temperature. At about 430 K, this material shows a change in crystal symmetry accompanied with one order of magnitude increase in its electrical conductivity and alterations in its optical properties. Although the property changes during the MIT in V3O5 are less pronounced than those observed in VO2, its transition temperature is 90 K higher, making it appealing for applications requiring elevated temperatures. In this article, the high-frequency characteristics were determined in a V3O5 two-terminal device in the range from 5 to 35 GHz. The S-parameters showed that the return loss at room temperature was close to −1.5 dB, and the isolation between ports was approximately −50 dB. At temperatures above the metal–insulator transition, the isolation decreased to around −40 dB at 35 GHz. For S11 and S22, similar behavior was observed at room temperature, with a notable change in the S-parameter phase of the device. This behavior suggests that V3O5 may function well as a capacitor because the considerable change in phase could control the flow of electrical signals in devices. This property also may be used for matching purposes, especially considering its response to temperature changes. Additionally, conductivity calculation from S-parameters shows a decrease of approximately two orders of magnitude at 500 K and one order of magnitude at 300 K compared to DC values. These findings highlight V3O5 potential for integration into radio frequency devices that demand consistent performance in high-temperature environments.