Digital signal

About: Digital signal is a research topic. Over the lifetime, 44213 publications have been published within this topic receiving 345279 citations.

Portable data device efficiently utilizing its available power and method thereof

Abstract: A portable data device (400) having a power controller (430), a clock generator (428) and a digital circuit (432). The power controller (430) has an output signal. The output signal is representative of available power. The clock generator (428) is coupled to the output signal of the power controller (430) for generating a variable clock rate corresponding to the output signal. The digital circuit (432) is coupled to the clock generator (428), and the digital circuit (432) is controlled by the variable clock rate.

Configuring digital functions in a digital configurable macro architecture

Abstract: A new digital configurable macro architecture is described. The digital configurable macro architecture is well suited for microcontroller or controller designs. In particular, the foundation of the digital configurable macro architecture is a programmable digital circuit block. The programmable digital circuit blocks can be configured to coupled in series or in parallel to handle more complex digital functions. More importantly, the configuration of the programmable digital circuit block is determined by its small number of configuration registers. This provides much flexibility. In particular, the configuration of the programmable digital circuit block is fast and easy since changes in configuration are accomplished by changing the contents of the configuration registers, whereas the contents are generally a small number of configuration data bits. Thus, the programmable digital circuit block is dynamically configurable from one predetermined digital function to another predetermined digital function for real-time processing.

Digital signal receiver for measurement while drilling system having noise cancellation

Abstract: A method is disclosed for reducing noise in a measured telemetry signal The method includes tracking a characteristic of at least one harmonic of a noise component in the measured telemetry signal band The at least one harmonic has a frequency outside a telemetry signal band The characteristic of the noise component is determined for at least one other harmonic thereof The at least one other harmonic has a frequency inside the telemetry signal band A noise reference is generated from the characteristic of the in band harmonic, and the noise reference is combined with the measured telemetry signal to generate a noise-canceled telemetry signal

Sequential detection of abrupt changes in spectral characteristics of digital signals

Abstract: The problem of sequential detection of abrupt changes in the spectral behavior of a digital signal is addressed. This problem arises, for example, in the sequential segmentation of nonstationary digital signals such as speech, (EEG) electroencepholograms, (ECG) electrocardiogram, and geophysical signals. The limitations of a classical test will be emphasized, and some new algorithms will be presented and compared via a simulation study and from a theoretical point of view.

Direct-sequence spread-spectrum digital signal acquisition and tracking system and method therefor

Abstract: A system and method of driect-sequence spread-spectrum TDMA (or TDD) digital communication, wherein acquisition and tracking occurs for a plurality of frames having a predetermined number of time slots. One of the predetermined number of time slots in each frame is assigned for acquisition purposes and carries acquisition and sync digital information. The remaining time slots in each frame have assigned header bytes for tracking purposes. The assigned acquisition time slot is spread with an acquisition direct-sequence spreading code. The remaining time slots are spread with a communication direct-sequence spreading code. During acquisition, the signal strength in each successive time slot for each spread frame is measured for a given number of time frames. The peak is located within the given number of time frames through a major acquistion sweep and a refinement sweep. The major acquisition sweep and refinement acquisition sweep locate the frame and time slot boundaries of the transmitted signal. Once acquired, tracking occurs during the header bytes of each successive remaining time slot. Acquisition, tracking and demodulation of the digital data is performed with the same circuitry.