Method and apparatus for determining signal components using digital signal processing
US5778027A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 24, 1995 |
| Grant date | Jul 7, 1998 |
| Priority date | — |
| Expiry date | Nov 24, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/2092
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Methods and systems for determining a cosine (I) or sine (Q) component for the purpose of modulating a digital signal in radiocommunication systems are disclosed. Exemplary embodiments describe how such determinations may be performed using digital signal processing techniques to improve component accuracy, while reducing the amount of processor memory (e.g., DSP memory) used to accomplish this task. Phase information from a sampled signal is used to access one or more tables containing component values, or a combination of a component base values and difference values between consecutive base values. The phase information can be used derive an offset value from the difference values, which offset value is added to a component base value to provide a component value for output. This has the effect of reducing the amount of memory consumed while maintaining high resolution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.