초록 ▼

Apparatus for generating elevation and azimuth reference signals for use in demodulating a tracking error signal to provide elevation and azimuth error components for use in adjusting the position of a tracking conical scan radar antenna, includes a template ring having a notched periphery and being

Apparatus for generating elevation and azimuth reference signals for use in demodulating a tracking error signal to provide elevation and azimuth error components for use in adjusting the position of a tracking conical scan radar antenna, includes a template ring having a notched periphery and being attached to a rotatable nutator of the antenna such that its peripheral notches are in a predetermined angular phase relationship with a reference position on a feed horn attached on the nutator, during rotation of the feed horn with the nutator. The apparatus further includes an optical transducer and electronic circuitry coupled thereto for producing the reference signals from a signal generated by the transducer in response to rotation of the ring with the nutator. As the ring rotates with the nutator, its notched periphery makes or breaks a photon path between light beam generating and sensing elements of the transducer. The sensing element then generates the signal which is received by the electronic circuitry. In addition to the two reference signals produced by the circuitry, a sync signal is generated and used internally within the circuitry to insure that the reference signals produced are in a proper phase relationship to the reference position on the feed horn of the nutator during rotation thereof.

대표청구항 ▼

In combination with a mechanism, such as a radar tracking antenna, having a frame, a member, such as a nutator device, mounted on said frame for rotation relative to said frame about a longitudinal axis and means for rotating said member, said member including an element thereon, such as a feed horn

In combination with a mechanism, such as a radar tracking antenna, having a frame, a member, such as a nutator device, mounted on said frame for rotation relative to said frame about a longitudinal axis and means for rotating said member, said member including an element thereon, such as a feed horn, which revolves about said axis as said member is rotated about said axis, an apparatus for generating a pair of reference signals being ninety degrees out of phase with one another and in a desired phase relationship to the angular position of said element during rotation of said member, said apparatus comprising: reference means attached on said member for rotation therewith about said axis, said reference means including first, second and third edge portions being disposed relative to one another for movement in a generally common rotational path upon rotation of said member, said second edge portion extending outwardly from and ninety degrees about the periphery of said member and having a pair of opposite ends, said third edge portion extending outwardly from and ninety degrees about the periphery of said member and having a pair of opposite ends with each end being displaced ninety degrees from a corresponding one of said opposite ends of said second edge portion, said first edge portion extending outwardly from the periphery of said member and being disposed between, but displaced at its opposite ends at known angular distances from, a corresponding one pair of said opposite ends of said second and third edge portions, said first edge portion being located at a reference position on said member having a known angular displacement from said element of said member such that said second and third edge portions are thereby disposed in a known phase relationship to the angular position of said element during rotation of said member; transducer means mounted on said frame adjacent the rotational path of said edge portions of said reference means for sensing both the presence and absence of any one of said edge portions in predetermined close proximity to said transducer means during movement of said edge portions in said path upon rotation of said member, said transducer means being operable to generate an electrical signal in response to sensing the presence of any one of said edge portions in said predetermined close proximity to said transducer means and in response to sensing the absence of any one of said edge portions in said predetermined close proximity to said transducer means; and electrical circuitry coupled to said transducer means and receiving said electrical signal generated by said transducer means, said electrical circuitry being operable to generate from said electrical signal a pair of reference signals being ninety degrees out of phase with one another and a sync signal for causing said reference signals to be generated in the desired phase relationship to the angular position of said element during rotation of said member.