Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Massive MU-MIMO-OFDM Uplink with Direct RF-Sampling and 1-Bit ADCs   Advances in analog-to-digital converter (ADC) technology have opened up the
possibility to directly digitize wideband radio frequency (RF) signals,
avoiding the need for analog down-conversion. In this work, we consider an
orthogonal frequency-division multiplexing (OFDM)-based massive multi-user (MU)
multiple-input multiple-output (MIMO) uplink system that relies on direct
RF-sampling at the base station and digitizes the received RF signals with
1-bit ADCs. Using Bussgang's theorem, we provide an analytical expression for
the error-vector magnitude (EVM) achieved by digital down-conversion and
zero-forcing combining. Our results demonstrate that direct RF-sampling 1-bit
ADCs enables low EVM and supports high-order constellations in the massive
MU-MIMO-OFDM uplink.

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The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
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The categories of this paper are: supr-con
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The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-lat
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The categories of this paper are: solv-int
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The categories of this paper are: acc-phys
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The categories of this paper are: funct-an
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The categories of this paper are: adap-org
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The categories of this paper are: nucl-th