321 results about "Total delay" patented technology

Optical variable delay devices for providing variable true time delay to multiple optical beams simultaneously. A ladder-structured variable delay device comprises multiple basic building blocks stacked on top of each other resembling a ladder. Each basic building block has two polarization beamsplitters and a polarization rotator array arranged to form a trihedron; Controlling an array element of the polarization rotator array causes a beam passing through the array element either going up to a basic building block above it or reflect back towards a block below it. The beams going higher on the “ladder” experience longer optical path delay. An index-switched optical variable delay device comprises of many birefringent crystal segments connected with one another, with a polarization rotator array sandwiched between any two adjacent crystal segments. An array element in the polarization rotator array controls the polarization state of a beam passing through the element, causing the beam experience different refractive indices or path delays in the following crystal segment. By independently control each element in each polarization rotator array, variable optical path delays of each beam can be achieved. Finally, an index-switched variable delay device and a ladder-structured variable device are cascaded to form a new device which combines the advantages of the two individual devices. This programmable optic device has the properties of high packing density, low loss, easy fabrication, and virtually infinite bandwidth. The device is inherently two dimensional and has a packing density exceeding 25 lines / cm2. The delay resolution of the device is on the order of a femtosecond (one micron in space) and the total delay exceeds 10 nanosecond. In addition, the delay is reversible so that the same delay device can be used for both antenna transmitting and receiving.

An apparatus and method for an analog fine delay line, a hybrid delay line, and a delay locked loop (DLL) is described. In the DLL, a coarse phase detector compares a reference signal and feedback signal in controlling coarse phase adjustment signals indicating whether a delay of a coarse delay line should be increased or decreased. Similarly, a fine phase detector compares the reference signal and feedback signal to generate a locking bias signal, which may increase or decrease a delay of an analog fine delay line. The analog fine delay line and coarse delay line may be connected in series creating the hybrid delay line having a total delay comprised of the coarse delay and the fine delay. Additionally, a fine bias generator may control the fine delay in response to an initiating bias signal from an analog phase generator or the locking bias signal.