UWB guided radar for arc detection

1
UWB guided radar forarc detection

• Riccardo Maggiora
• Politecnico di Torino

2
UWB

• The next generation of Guided Radar (GUIDAR) is
  based on Ultra Wide Band (UWB) radar signal
  processing
• As spread spectrum technology has revolutionized
  the communications industry UWB is dramatically
  improving radar performances
• These advanced signal processing techniques are
  adapted to coaxial cable technology to provide
  new features and enhanced performance on arc
  detection

3
Principle of Operation

• UWB signals (properly chosen to reduce sidelobes
  and to improve accurancy) are transmitted along
  the main transmission line at a PRF and the
  echoes are received by means of directional
  couplers
• The core of the receiver is an ultra high-speed
  correlator implemented in a Digital Signal
  Processor (DSP)
• This ultrahigh speed correlation process involves
  the addition and subtraction of the sampled
  in-phase and quadrature-phase received signal

4
Principle of Operation

• PRF (pulse repetition frequency) is around 1 MHz
  (arc is detected in 1 µs)
• PCR (pulse chip rate) is around 100 MHz and PCN
  (pulse chip number) is about 64
• Modulation is BPSK and carrier frequency is
  around 500 MHz

5
Radar Principles

• The background scattering is extracted from the
  received signal at any pulse
• If a target (arc) is detected an alarm is raised
• The arc radar cross section is detected and
  classified
• Orthogonal complementary codes can be transmitted
  on coaxial cables. The orthogonal nature of the
  code allows the composite coded pulse response to
  be de-multiplexed into the independent responses
  or to be used for sidelobes suppression techniques

6
Radar Principles

• Improved performance will be obtained through
  calibrated thresholding
• Software segmentation of the cables for creating
  sensed and non-sensed zones is easy to be
  implemented

7
Conclusions

• The radar is resilient to the background
  structure of transmission lines (bends, T
  junctions, windows, etc.) and to the antenna load
  variations
• locating the arc along transmission lines is easy
  (large RCS)
• recognizing the type of arc by means of its radar
  cross section is possible
• The proposed system reduces the cost of arc
  detection systems with respect to actual systems