Abstract: Methods and apparatus to implement compact time-frequency division multiplexing for MIMO radar are disclosed. An apparatus includes an antenna array controller to: transmit a first signal via a first transmitter of a radar antenna array, the first signal having a first duration and modulated across a first frequency range; and transmit a second signal via a second transmitter, the second signal having a second duration and modulated across a second frequency range, the first and second durations including an overlapping period of time, the first and second frequency ranges including an overlapping frequency range. The apparatus further includes a signal separation analyzer to: determine a first echo received at a receiver of the radar antenna array corresponds to the first signal; and determine a second echo received at the receiver corresponds to the second signal.

Abstract: Method for calculating model parameters for a coil (L), comprising of: incorporating the coil into a converter (1) with a switching element (2); connecting a resistive load (9); applying an input voltage (Uin); controlling the switching element in order to obtain a periodically varying voltage across the coil; measuring at least a first and second quantity representative of respectively the voltage (UL) across and the current (iL) through the coil; determining at least one voltage value and at least one current value on the basis of the measured first and second quantity; calculating a loss resistance and/or a loss power of the coil on the basis of the at least one voltage value and the at least one current value.

Abstract: The present invention provides a display parameter adjusting method and an electronic device employing the method. The electronic device includes a display, a light source and a light receiver. The display parameter adjusting method includes: emitting a light beam to the light receiver by the light source; calculating a turbidity of a location of the display according to a first light intensity of the light beam received by the light receiver, wherein a propagation direction of the light beam emitted by the light source is parallel to a displaying surface of the display, and the location is beneath a water surface; and adjusting the display parameter according to the turbidity.

Abstract: A lamp tube switching circuit includes a first connector and a second connector for connecting either an LED lamp tube or a fluorescent type lamp tube, a switch module being a mechanical switch including first, second and third switches, a starter and ballast. Each of the first and second switches has a static terminal for connecting with a power supply, and four dynamic terminals for selectively connecting with the static terminal thereof. Different circuits can be configured by adjusting the connection between the static and dynamic terminals, wherein each circuit can drive a selected type of lamp tube to generate light.

Abstract: A display system capable of raising limits on the response speed of the spatial light modulator and the rate of pulse-width modulation signal transfer is provided at a low cost. The display system comprises: a color switch filter unit used in the sequential color separation of white light from the light source; a spatial light modulator which is illuminated by lights of plural color elements from the color switch filter unit and generates image lights of the respective color elements; and an intensity switch filter unit for switching three or more intensity levels of the respective lights of plural color elements, being separate from the color switch filter unit.

Abstract: A display system capable of raising limits on the response speed of the spatial light modulator and the rate of pulse-width modulation signal transfer is provided at a low cost. The display system comprises: a color switch filter unit used in the sequential color separation of white light from the light source; a spatial light modulator which is illuminated by lights of plural color elements from the color switch filter unit and generates image lights of the respective color elements; and an intensity switch filter unit for switching three or more intensity levels of the respective lights of plural color elements, being separate from the color switch filter unit.

Abstract: Cathode ray tube display apparatus includes a cathode ray tube having a screen (210) and a neck (350). In use an electron beam is directed from the neck (350) towards the screen (210) along an axis (S) of the cathode ray tube containing the centre of the screen (210). However, deflection means (320) mounted on the neck (350) deflects the beam from the axis (S) at a deflection centre (X) of the cathode ray tube to scan the beam across the screen (210) in a raster pattern. Raster rotation means (300, 310) permits rotation of the raster pattern about the centre of the screen (210). The raster rotation means (300, 310) includes first and second coils. The first coil (300) is located around the neck (350) at or near the deflection centre (X) to generate, in use, a first magnetic field in the path of the electron beam.

Abstract: There is provided a sine wave deflecting circuit having a resonance circuit comprising a deflecting coil and a resonance capacitor and a circuit for detecting a signal waveform of the resonance circuit and for driving the resonance circuit on the basis of the detection signal, in which the deflecting coil is sine-wave driven by the self-oscillation. A rectangular wave driving circuit which is constructed by connecting first and second switching elements such as FETs through a capacitor is provided at one end of the deflecting coil.

Abstract: A circular, ziz-zag scan for use with vidicon tubes. A sine wave is generated, rectified and its fourth root extracted. The fourth root, and its inverse, are used to generate horizontal ramp and sync signals. The fourth root is also used to generate a vertical sync signal, and the vertical sync signal, along with the horizontal sync signal, are used to generate the vertical ramp signal. Cathode blanking and preamplifier clamp signals are also obtained from the vertical sync signal.

Abstract: A system for rotating images on a raster display device through an angle includes a tilt angle signal, first and second tilt angle sine function modulators and first and second tilt angle cosine function modulators. The horizontal deflection circuit of the display device is driven by a ramp signal which is the sum of the horizontal sweep generator output multiplied by the second cosine function modulator plus the vertical sweep generator output multiplied by the second sine function modulator. Similarly, the vertical deflection circuit of the display unit is driven by a ramp signal which is the sum of the vertical sweep generator output multiplied by the first cosine function modulator plus the horizontal sweep generator output multiplied by the first sine function modulator. Variation of the tilt angle signal varies the sine and cosine functions and produces a corresponding rotation of the display image.

Abstract: By analyzing the spatial-frequency spectrum of a high-resolution image into a low-pass remnant subspectrum band having a nominal high-frequency cutoff below that of one or more other spatial frequency bands, and separately transmitting each band, starting with the remnant band, over a narrow-band communication channel from a transmitter to an image display at a remote receiver, useful information as to the image contents is available more quickly to the viewer of the display than by past methods of transmitting high-resolution image information over a narrow-band communication channel for display.

Abstract: A sweep termination generating circuit adopts an octagon boundary for sweep termination which is set by combining a plurality of comparators so as to be circumscribed about the display screen of a circular CRT. When the sweep position is deviated from the center of the display screen for the purpose of displaying a radar image by PPI sweep, the circuit allows the comparators to detect that a scanning signal for scanning an electron beam from the off-center sweep position has reached the boundary for sweep termination and thereby generates a sweep termination signal.

Abstract: A PPI display apparatus allows a radar image or bearing marker to be displayed on a circular CRT screen through sweeping on the basis of a plan position indicator system. In the apparatus, the generation of a radar antenna angle signal, generation of a bearing angle signal representing the angle of a bearing cursor, generation of an antenna angle signal corrected by adding a deflection angle to the antenna angle, and generation of sine and cosine signals corresponding to the antenna angle or bearing angle are all carried out through digital processing.

Abstract: A cathode ray tube display device having beam deflection coils (8,10,12,14) and means (44 and 46) for applying to inductive means (58 plus the coils) which includes the beam deflection coils a voltage for causing a ramp current to flow in the coils to produce progressive beam deflection, comprising means (52,54,56) for selectively modifying interconnections between the coils to change the inductance presented to the voltage applying means and thus change the gradient of the ramp current and the rate of beam deflection, said interconnection modifying means being operable to change the number of deflection coils through which said current flows.

Abstract: A sweep generator for producing a circular raster of curved scanning lines on the target surface of a video camera is disclosed. Each curved trace follows a substantially circular path through a scanning angle of 360.degree.. The circular raster is generated by horizontal and vertical scanning signals which are synchronized with the horizontal line frequency of a video receiver. The horizontal scanning signal is characterized by a constant amplitude component followed by a sine wave component, and the vertical scanning signal is characterized by a composite waveform including a constant amplitude component followed by a sine wave component which is shifted 90.degree. in phase with respect to the sine wave of the horizontal scanning signal.

Abstract: A raster generator for producing a raster-type display on a random scan dlay terminal where the raster can be oriented at any selected angle of rotation. The rotating raster generator responds to a digital input signal representing the desired angle of rotation which may represent, for example, the turning or rolling motion of a vehicle. The generator operates digitally to provide an output comprised of two sets of digital signals, each signal set representing an axis rotated in an amount directly related to the value of the input angle. The signals are presented as inputs to the deflection coils of a cathode-ray tube (CRT) or like display.

Abstract: A digital apparatus for generating a raster whose scan parameters can be ered and controlled by an external program. In addition to standard horizontal sweep, the raster can display a "waterfall" scan, range bearing sweep and various other geometrical patterns. A selector switch permits the raster scan unit to be selectively connected to either a computer or a control panel which provide the parameters for specifying any one raster.

Abstract: A system for performing real time quantization and analog/digital conversion of an analog waveform operating with analog input signals over one gigahertz bandwidth is realized by utilizing a CRT type device in which the electron beam is deflected by the analog input waveform. The deflected electron beam strikes a fast phosphor screen and an externally positioned target consisting of light sensitive elements arranged in a discrete pattern detects and quantizes the signal. The output of the detectors feed an encoder resulting in a binary digital output waveform. The device accepts both unipolar and bipolar video waveform and has parallel output channels such that further circuitry to be employed can operate with reduced bandwidths.

Abstract: A radial sweep generator circuit generates a series of radial sweep lines in succession to simulate a rotating sweep line which extends from the center of a video display to the periphery of the display. The display consists of a rectangular matrix of display positions arranged in lines and columns which are scanned in a raster scanning format. A vector number generator generates a vector number signal corresponding to one of the radial sweep lines which is to be displayed. A vector origin counter determines the display position on the periphery of the matrix from which the sweep line is to originate. A vector line generator is responsive to the vector number generator and to the vector origin counter for providing video display pulses.

Abstract: A radar system in which the time duration of video pulses corresponding to echo returns is increased as a direct function of the range of the return. On a PPI visual indicator, the visibility of long range targets is thus enhanced by increased size without distorting the display of short range targets and clutter.

Abstract: The apparatus generates a train of pulse signals in real time which are fed to a Plan Position Indicator radar display video bright-up circuit. A line is formed on the display at a bearing .theta..sub.R , the direction of a VHF/DF fix, and passes through a point having the coordinates R.sub.o, .angle..theta..sub.o .degree., the position of the VHF/DF receiver, with respect to the center of the plan position indicator rotating radial scan. The radial scan operates at a radar trigger pulse repetition frequency F and rotates at a frequency f to subtend an angle .DELTA..theta.=360.degree..times.f/F per scan. The apparatus includes an up-counter for storing a count of R.sub.o sin (.theta..sub.R -.theta..sub.o), and a down-counter coupled to the up-counter and enabled at the pulse repetition frequency F to receive the count from the up-counter. The down-counter is adapted to provide an output pulse signal to the video bright-up circuit when its count reaches 0.

Abstract: An arc-scanned sector cathode ray tube display system achieves constant writing speed by developing trigonometric X and Y deflection signals with amplitude linearly decreasing and scan rate linearly increasing as arcs are drawn from periphery toward apex of the display sector. Video/deflection synchronism is achieved by development of a video clock pulse train comprised of selected pulses from a clock source by means of which displayed video bits are shifted from rho-theta formated storage on a time/position basis such that video and beam position are synchronized to within one displayed picture element throughout the sector display.

Abstract: An analog-to-digital converter includes a common input amplifying device such as a transistor in differential amplifier relationship with each of a plurality of output amplifying devices, one for each voltage range converted to digital form.Separately controllable circuits are provided for: (A) setting a video display screen signal to the threshold of visibility, and (B) increasing the brightness of the screen to various levels above the threshold in accordance with digital signals from the analog-to-digital converter as modified by a brightness control.

Abstract: In a CRT display exhibiting a Rho-Theta format where certain of the lines would normally extend beyond the edges of the CRT screen, feedback signals from at least a deflection coil are used to terminate display lines at the edge of the screen and to initiate immediate retrace. Compensation is applied to at least a deflection voltage to compensate for display line bunching caused by unequal scan line times.

Abstract: Circuit to apply an offset voltage to be added to a charge storage signal depositing a charge on a radially swept charge storage surface so that the charge storage signal is a minimum at the center of the surface and a maximum at the outer edges of the sweep. This reduces or eliminates the charge integration in the area where the sweep lines converge.

Abstract: According to one embodiment, distinctive indicia having a "three-dimensional" appearance and representative of well logging data is produced by a CRT (Cathode-ray tube) recorder by modulating both the intensity and position of the sweeping electron beam in response to variations in the data. In another embodiment, distinctive indicia in the form of a vector or arrow representative of the data is produced by sweeping the CRT electron beam in such a way that it defines an increasing spiral pattern. The electron beam is then turned on for a short pulse at the same angular position of each cycle of the spiral. For purposes of synchronization, in each of the above embodiments the beam sweep is initiated by a recurring event, such as a pulse indicative of a given incremental change in the depth level from which the data was derived.

Abstract: High speed, spiral scan display apparatus capable of producing distortion free visual presentations from stored video data, and a method for preventing occurrence of visible distortion caused by switching transients in such apparatus. The visual presentations are generated by display writing means which traces a circular path on a display area. The radius of the circular path is periodically incremented to provide for scanning the entire display area. Visible distortion resulting from rapidly changing the path radius is prevented by blanking the display writing means for an interval of time immediately following each radius change. Data storage requirements are minimized by ordering and retrieving video data so that only data sequentially needed during unblanked intervals is supplied to the display writing means.

Abstract: Apparatus for forming graphical configurations, such as alphanumeric characters, on a radiant energy surface, such as the face of a cathode ray tube, with an energy beam. The apparatus includes a path segment length command means which serves to provide a series of sets of coded command signals. Each set of coded command signals defines the length of an associated path segment of a path to be traced on the surface. A beam controller serves to deflect the beam to trace a predetermined scan path on the surface starting from a preselected starting location. The path includes a plurality of successive path segments which are of lengths dependent upon associated successive sets of coded command signals. These path segments alternate between being inside and outside of the area of a configuration to be formed on the surface. The beam is controlled such that it is continuously blanked while tracing the segments which are outside of the configuration area.

Abstract: In a PPI display type radar system wherein a sector shaped unit scanning surface is established in a scanning plane and a unit scanning surface is shifted progressively in the radial and circumferential directions to seach the received pattern for judging a target. The received pattern is identified by dividing the unit scanning surface into a plurality of annular sections derived from a plurality of concentric circles. The scanning unit for scanning surfaces having approximately the same area over the entire scanning surface is designed in such a manner that the ratio (percentage of extraction) of a number of sampled scanning beams to the number of actual scanning beams is a maximum when scanning an annular section which is located most remotely from the center. The percentage of extraction is gradually decreased toward the center so that the percentage of extraction becomes a minimum 1/n (where n is an integer) when scanning an annular section closest to the center.

Abstract: In a radar PPI display, digital techniques are utilized to allow an operator to move the point about which the radial trace beam rotates to a point remote from the center of the radar viewing screen and including movement off the screen without actually moving the display beam off the screen. A sweep signal generator detects the location of the operator positioned off-center point from the settings of off-center controls and is responsive to radar range scale and antenna position signals to generate appropriate ramp deflection signals in the proper time sequence to accurately display a selected portion of the plan position indication upon the entire area of the viewing screen. A beam control circuit is responsive to the same signals as the signal generator and to a radar start pulse to determine the exact time the PPI display beam is to be turned on to display selected portions of the plan position indication.

Abstract: Ultrasonic probe apparatus for real time B-mode sector scan examination of a cross section of a structure such as the human heart. A transducer is pivotally mounted near an end of an elongated housing, and linkage means are provided in the housing for oscillating the transducer about an axis whose plane is approximately perpendicular to the longest dimension of the housing. Means are provided for causing the transducer to produce ultrasonic pulses which are reflected by interfaces of the object under examination, and the echoes from these interfaces are returned through the transducer to a B-mode display system. A B-mode sector sweep circuit is provided to produce a B-mode display of the echo pattern received from the structure being observed.

Abstract: An electron-optical image tube is provided which avoids the limitations imposed by photographic and image storage techniques and which enables a direct linear intensity profile of a pulse train to be obtained. The image tube, instead of having a phosphor screen, has a disc with one or more slit apertures therethrough and a photoelectron image is scanned across the aperture or apertures. The time spacing of the light pulses can be adjusted so that the time of the image tube coincides with the fixed aperture or apertures in the disc when a continuous circular scan is used.