摘要:
A digital data receiver includes tunable analog components having variable parameters that are responsive to the bit error rate (BER) of the decoded digital data. The analog components include a quadrature generator having a tunable phase shifter, an analog filter having a tunable bandwidth, a tunable magnitude equalizer circuit, a tunable group delay equalizer circuit, and an amplifier having an adjustable gain. The tunable components are controlled by tuning control signals that incorporate digitally-produced fine tuning signals. The digital tuning signals are altered in accordance with realtime changes in the BER.
摘要:
A branch metric processor for use in a maximum-likelihood convolutional decoder accepts a set of soft-decision symbols, an indicator of a level of quantization thereof and a set of erase control signals and generates branch metrics for base code rates of 1/3 and 1/2. The apparatus represents a substantial reduction in complexity over prior art devices. Erasure of selected symbols allows the processor to generate branch metrics for higher code rates and is advantageous in very low code rate applications.
摘要:
An automated device facilitates the assembly a surgical instrument that includes a knife with a high aspect ratio. The automated device includes a fixture for restraining a subassembly of the surgical instrument that includes the knife. A blade grip on the device is movable relative to the fixture, and is configured to urge the knife into a restrained position in the subassembly suitable for the subsequent assembly of an additional instrument component. A grip actuator is provided to move the blade grip.
摘要:
An automated device facilitates the assembly a surgical instrument that includes a knife with a high aspect ratio. The automated device includes a fixture for restraining a subassembly of the surgical instrument that includes the knife. A blade grip on the device is movable relative to the fixture, and is configured to urge the knife into a restrained position in the subassembly suitable for the subsequent assembly of an additional instrument component. A grip actuator is provided to move the blade grip.
摘要:
A video lighthead mountable to a video camera and having a dimmer control that varies the intensity of the light output from the lighthead using pulse width modulation techniques. A photo sensor measures the intensity of light reflected from a subject in front of the lighthead. The intensity of light output from the lighthead is adjusted by control circuitry in response to changes in measured reflected light intensity to maintain a constant level of illumination. The adjustment is carried out by modifying the duty cycle of a pulse width modulation circuit. The duty cycle adjustment of the pulse width modulation is also used to compensate for supply voltage variations in order to maintain constant light output.
摘要:
A compact AC-DC motor comprising a housing having a center section and respective end bells, each having a recess therein. A stator is received in the housing and extends into the recess in one end bell and a magnetic pole piece is similarly received in the housing and extends into the recess in the other end bell. Rotatably supported in the end bells is a shaft which mounts a rotor which cooperates with the stator, and an armature winding in juxtaposition to the rotor which cooperates with the pole piece. Additionally, a brush holder is affixed to the end of the pole piece whereby the construction provides a highly efficient motor which occupies a minimum volume of space.
摘要:
A viewfinder assembly for a camera having a door for access to the interior wherein the viewfinder, when properly positioned to permit pictures to be taken, blocks the door. The assembly comprises a support barrel mounted on a camera lens and a main body section adapted to support optical elements therein. An eyepiece is at one end of the main body section and extends outwardly therefrom. The invention includes mounting means for rotatably mounting the main body section on the support barrel to permit rotation of the viewfinder assembly to a position wherein the door is no longer blocked.