FFT Spectrometer, Second Generation

Omnisys second generation FFT spectrometers are developed to meet the increasing demand for processed bandwidth. The new and improved product offers faster, more powerful processing at speeds up to 5000MHz and 10Gsps.

The second generation FFT Spectrometers from Omnisys were developed using our previous experience and technical know-how from designing, producing and implementing our first generation of FFT Spectrometers. The main focus was on substantially improving the processing performance. For signal processing, we are using a Virtex-6 FPGA and new firmware can be loaded using the same USB2.0 interface as for data communication. The firmware FFT design is typically using a polyphase filterbank, FFT core of 16k channels, power calculation and accumulation. Switching between two buffers for data accumulation reduces the integration idle time to almost zero.


  • The new FFT Spectrometers provide an impressive eight separate analog inputs which can be processed simultaneously in either real single-sideband transmission, SSB, or complex  double sideband transmission, DSB, mode. The sampling clock is generated internally but can be provided using an external SMA connector.
  • The power generation and distribution is controlled locally, reducing the number of external power rails to only one. The main data interface is a Hi-Speed USB 2.0 but, for demanding applications with high data throughput, an extra gigabit port is available using an eSATA connector. Up to ten general purpose IOs can be used for custom functionality, such as hardware controlled integration start/stop and input blanking.
  • The 10-bit ADCs are highly configurable, giving users the possibility to switch between almost any inputs dynamically. Calibration registers are also available to match the input offset, gain and phase. A small EEPROM can be used to hold startup and calibration settings unique to each module.
  • Custom made designs are available.


  • Mainly radio astronomy applications.