Modulating array QAM transmitter
US5612651A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 2, 1996 |
| Grant date | Mar 18, 1997 |
| Priority date | — |
| Expiry date | Jan 2, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/22
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
This invention pertains to a method for producing high power microwave transmission signals conveying one of a plurality of symbols, wherein a symbol represents a plurality of bits, and also to a modulating array transmitter that operates in accordance with the method. The method includes a first step of applying j bits to a data storage device to address the data storage device to output N bits to N/2 QPSK modulators. Each of the N/2 QPSK modulators receives a subset (a pair) of the N bits. Each of the bit pairs specifies one of up to four phase shifts. Within each of the N/20 PSK modulators, a next step phase modulates a reference (e.g., local oscillator) signal in accordance with a phase shift specified by the received pair of bits. A next step amplifies the outputs of each of the N/2 QPSK modulators to produce respective amplified QPSK modulated signals. A further step combines the amplified OPSK modulated signals by vector addition to produce one of a plurality of symbols, wherein the produced symbol represents a value of the j (even number) input bits. Also disclosed is a BPSK embodiment of the invention, wherein there are N BPSK modulators, each receiving one of the N bits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.