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Abstract The role of manganese (Mn) in ecosystem carbon (C) biogeochemical cycling is gaining increasing attention. While soil Mn is mainly derived from bedrock, atmospheric deposition could be a major source of Mn to surface soils, with implications for soil C cycling. However, quantification of the atmospheric Mn cycle, which comprises emissions from natural (desert dust, sea salts, volcanoes, primary biogenic particles, and wildfires) and anthropogenic sources (e.g., industrialization and land‐use change due to agriculture), transport, and deposition, remains uncertain. Here, we use compiled emission data sets for each identified source to model and quantify the atmospheric Mn cycle by combining an atmospheric model and in situ atmospheric concentration measurements. We estimated global emissions of atmospheric Mn in aerosols (<10 μm in aerodynamic diameter) to be 1,400 Gg Mn year⁻¹. Approximately 31% of the emissions come from anthropogenic sources. Deposition of the anthropogenic Mn shortened Mn “pseudo” turnover times in 1‐m‐thick surface soils (ranging from 1,000 to over 10,000,000 years) by 1–2 orders of magnitude in industrialized regions. Such anthropogenic Mn inputs boosted the Mn‐to‐N ratio of the atmospheric deposition in non‐desert dominated regions (between 5 × 10⁻⁵and 0.02) across industrialized areas, but that was still lower than soil Mn‐to‐N ratio by 1–3 orders of magnitude. Correlation analysis revealed a negative relationship between Mn deposition and topsoil C density across temperate and (sub)tropical forests, consisting with atmospheric Mn deposition enhancing carbon respiration as seen in in situ biogeochemical studies. 

This paper presents a multiphase switched-capacitor power amplifier (MP-SCPA). Cartesian combining architectures suffer reduced output power and efficiency owing to combination of out-of-phase signals. The multiphase architecture reduces the phase difference between the basis vectors that are combined, increasing the output power and efficiency compared to the Cartesian combiners. 16 equally spaced phases are produced by a phase generator with each phase's relative amplitude weighted on the bottom plate of a capacitor array and combined on a common top plate, resulting in linear amplification. The MP-SCPA delivers a peak output power and PAE of 26 dBm and 24.9%, respectively. When amplifying an LTE signal the average output power and PAE are 20.9 dBm and 15.2%, respectively while achieving <¿¿¿30 dBc ACLR and 3.5 %-rms EVM. 

An envelope elimination and restoration (EER) transmitter that comprises a class-E power amplifier and a digitally controlled current DAC modulator is presented. A switched capacitor DAC is designed to control an open-loop transconductor that operates as a current modulator, modulating the amplitude of the current supplied to a class-E PA. Such a topology allows for increased filtering of the quantization noise that is problematic in most digital PAs (DPA). The system measurements yield a peak output power and power added efficiency (PAE) of 22.5 dBm and 23.6%, respectively. When applying a WCDMA signal, the measured EVM is 1.32% and the adjacent channel power ratio (ACPR) is -37.9 dBc, while outputting 19.9 dBm at 14.3% PAE. For an LTE signal, the measured EVM is 3.72% and the ACLR is -30.2 dBc, while outputting 18.1 dBm at 10.6% PAE.