User's Manual

14 Ultra Wideband Perimeter Surveillance Pole / User’s Manual
3. P400 Radar
The radar is Time Domain’s P400 Ultra Wideband (UWB) module (Figure 13) configured to
provide monostatic and bistatic radar operation. Monostatic radar operation is a single device
receiving scans from its own transmitted pulses. In a bistatic mode one radar receives scans
(pulses) transmitted from another radar. The receiving radar first acquires the transmitted
energy and establishes a common time base with which to receive the scans.
Data communication for the P400 is over Ethernet. Each P400 is configured with a static IP
address. Scan data is sent from the P400 over Ethernet to the server. The server also sends
control and configuration data to the P400s over the Ethernet, either directly to a specific
P400 (i.e. IP address) or by broadcasting to all P400s.
Figure 13: P400 UWB Module
3.1 P400 Radar Theory of Operation
The P400 UWB radar transmits high bandwidth (narrow) Gaussian pulses. With a center
frequency of 4 GHz and a bandwidth of 2 GHz (see Figure 14) the waveform supports a
resolution of a few centimeters. The UWB radars receive the pulse response in either a
mono-static mode or bi-static mode. Each radar’s precision on-board timing allows it to
operate as a mono-static device where it first transmits a pulse and subsequently receives the
pulse response. In the bi-static mode, one radio transmits the pulse and another radio receives
the response. In order to enable bi-static operation the transmitted waveform includes an
acquire sequence that allows the receiving radio to “find” the transmitted pulses in time.
Once found, a code embedded in the polarity of the transmitted pulses allows the receiving
radios to synchronize with the transmitter. When multiple receivers receive the same
transmitted pulse response this is termed the multi-static mode; this mode is fundamental to
the system. Within the system a complete pulse response is known as a scan. The sequence
of scans between a specific transmitter and receiver pair is a link. As discussed in Paragraph