Radar Signal Exciter Unit

Introduction: EXCITER-1.0 is a Radar Signal Exciter Unit which can be used to generate the transmit radio frequency (RF) pulse signal of a typical pulsed radar system. EXCITER-1.0 unit is user configurable for RF signal frequency over a wide band and can generate periodic, coded or uncoded RF pulses as per user configuration. This unit performs coding of the RF signal as per the Tx code input digital signal using bi-phase (0 and 180 deg) modulation. EXCITER-1.0 supports a wide range of transmit code lengths, transmit pulse widths and pulse repetition rates. The Tx_Code input is assumed to be as per the requirements of pulse coding i.e. complimentary or barker codes. EXCITER-1.0 unit can also generate other modulation schemes such as AM, FM, FSK and arbitrary chirps.

Typical Applications :

  • Pulsed Radar System Implementation (Wind Profiler, Weather Radar, Cloud Radar, Ionospheric Radar etc.)
  • FMCW Radar Processor (RF pulse outputs generate chirp RF signals)
  • RF Waveform Generation for custom requirements

EXCITER-1.0 Description :

This unit uses state of the Micro-Controller Unit (MCU) and Direct Digital Synthesis (DDS) chip technologies to implement the function of coded or un-coded radar RF pulse generation. The MCU accepts configuration parameters such as RF frequency, RF amplitude from a host computer over RS422 or ethernet interface and controls the DDS device for generation of continuous wave (CW) RF signal. The DDS device can be locked with the Master Sync Clock input to the EXCITER unit.

The DDS output CW RF signal or an external CW RF signal is passed through a bi-phase coder module to generate phase modulated RF pulse signal as per the timing specified by the Tx timing signals namely Tx_Pulse and Tx_Code. The MCU also manages critical administrative functions such as EXCITER-1.0 configuration, monitoring, diagnostics etc. EXCITER-1.0 offers two communication interfaces namely 10/100 Mbps ethernet port and an RS422 port. All internal and timing/control signal output from EXCITER can be synchronized with an external clock source using internal Phase Locked Loop (PLL).  

EXCITER-1.0 can also be run in an internal mode in which the MCU generates Tx_Pulse and Tx_Code signals based on the configuration. These signals are used for modulation in the bi-phase coder module and are also output on panel connectors for external system configuration.

EXCITER-1.0 Specifications:

Serial No.ParametersSpecification
1No. of RF Pulse Output Channels1 (More channels available as option)
2RF Pulse frequency range1MHz to 1000MHz
3RF pulse maximum output level0dBm (LNA option available)
4Tx Timing signal inputsTx_Pulse and Tx_Code
5Tx Timing signal inputs voltage complianceLVTTL
6Master sync clock input frequency10MHz (configurable)
7Master sync clock input amplitude0dBm (minimum)
8Communication interfacesRS422 (1), 10/100 Ethernet (1)
9Physical characteristics500mm x 482mm x 88mm , 8 kg
10Power supply input28VDC, 2A  (Other options available)
11Operating temperature range0 to 50 degC
12Application Programming InterfaceMS-Windows and Linux based APIs for creating user specific applications. EXCITER-1.0 is compatible with SCI-COM’s RC SW Application for Radar Control and WindPro SW application for Wind Profiler Data Products.