Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Software-based Low-Jitter Servo Clock for Inexpensive Phasor
  Measurement Units   This paper presents the design and the implementation of a servo-clock (SC)
for low-cost Phasor Measurement Units (PMUs). The SC relies on a classic
Proportional Integral (PI) controller, which has been properly tuned to
minimize the synchronization error due to the local oscillator triggering the
on-board timer. The SC has been implemented into a PMU prototype developed
within the OpenPMU project using a BeagleBone Black (BBB) board. The
distinctive feature of the proposed solution is its ability to track an input
Pulse-Per-Second (PPS) reference with good long-term stability and with no need
for specific on-board synchronization circuitry. Indeed, the SC implementation
relies only on one co-processor for real-time application and requires just an
input PPS signal that could be distributed from a single substation clock.

14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
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The categories of this paper are: hep-lat
2
The categories of this paper are: math
16
The categories of this paper are: stat
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an
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The categories of this paper are: eess
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The categories of this paper are: adap-org