What is an Optical Delay Line-- ODL?

  • An Optical Delay Line (ODL) is an electric-optic-electric tool. It carries out fixed dead time( s), in between a few split seconds as much as a number of hundred split seconds, for signals from 10MHz approximately 40GHz as well as more. Low-frequency ODL versions are varying from 10MHz to 6GHz. The high-frequency ODLs versions depend on 8GHz, 15GHz, 18GHz, 20GHz, and 40GHz.

    On a more technological level, the input signal is converted into an optically regulated signal. The optical signal is transferred right into a lengthy single-mode fiber, typically at a 1.55-micron wavelength or similar. Passing the fiber, the optical signal is converted back right into an electrical RF signal. The electric control on the ODL chooses the optical system immediately, without demand for any type of adjusting by the operator.

    An Optical Delay Line system (ODL) also incorporates high-performance lasers such as DFBs, optical modulators for high procedure frequencies, photodiodes, and additionally other parts such as optical diffusion compensators, optical buttons, optical amplifiers, and pre-and-post NEON amplifiers to provide extremely high performance. The ODL optical system supports very high data transfers of analog signals, high sensitivity with a vast dynamic range, for various delays.

    Variable Optical Delay Lines ( also called Progressive ODLs) are made use of in a selection of applications including radar array simulation as well as signal processing. The Progressive ODL has a few hold-up lines using the very same transceiver where the customization is done.

    One of the most usual practical strategy for a variable hold-up system is an ODL system arrangement that includes cascaded 1:2 as well as 2:2 optical matrices with several different delay lines in between (replacing the above two optical switch matrices 1:8). This plunged button matrix is a Progressive Delay Configuration which is shown listed below.

    The desired mix of delay lines is chosen to define the called for delay. In the diagram listed below, there are 4 dynamic hold-up lines with plunged button matrices. In such a configuration, the individual can pick any one of the 16 mixes of feasible delay worths (16= 24). For instance, a hold-up can be picked which is equivalent to Dtot= D1+ D2 +D4, or Dtot= D3+ D4, and so on).

    Modern Optical Delay Line setup includes 4 2:2 optical buttons, providing 16 different hold-up lengths.

    In some cases, dispersion compensation is required when the signal regularity and the delay line size rise, leading to the optical signal being dispersed and weakened significantly. As NEON, we fix this issue by integrating DCM (Dispersion Compensation Module) in our Optical Delay Line (ODL) options.


    It does fixed time hold-up( s), in between a few nanoseconds up to several hundred microseconds, for signals from 10MHz up to 40GHz and more. The preferred combination of hold-up lines is selected to define the needed hold-up. In the layout below, there are 4 modern hold-up lines with plunged button matrices. In such a configuration, the individual can choose any of the 16 combinations of possible delay worths (16= 24).