 TFO resynchronization system |
| An embodiment of the invention provides a method of maintaining synchronization of an inband ... |
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| Optical data bus having a statistical access method |
| In an optical data bus of the above species, the object of the present invention is to obtain, ... |
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| Circuit and method for signal transmission |
| Bearing in mind the above-described problems with the prior art techniques, the present invention ... |
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| Non-volatile RAM cell with enhanced conduction insulators |
| What is claimed is: 1. A memory system comprising; a semiconductor substrate, a volatile memory ... |
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| Target location systems |
| What we claim is: 1. A target location system comprising a signal transmitter including a pair of ... |
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| Multiple bit output dynamic random-access memory |
| An improvement for a dynamic random-access memory which includes memory cells coupled to sense ... |
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| Autonomous N-modular redundant fault tolerant clock system |
| In accordance with the present invention, a fault tolerant clock system comprises a first set of ... |
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| Expandable digital error detection and correction device |
| What is claimed is: 1. An error detection and correction device (300) comprising in combination: a ... |
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| Automated safestore stack generation and move in a fault tolerant central processor |
| What is claimed is: 1. A fault tolerant central processing unit comprising: A) data manipulation ... |
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Multiple channel quadrature communication system and method
| Details |
Inventors: Zscheile, Jr., John W.; Wilson, Michael L.; Saggio, Richard J.; Lundquist, Alan E.;
Assignee: Unisys Corporation (Blue Bell, PA)
Primary Examiner: Chin; Wellington
Assistant Examiner: Vu; Huy D.
Attorney, Agent or Firm: Sowell; John B., Starr; Mark T., Scott; Thomas J.
A transmitter is provided which simultaneously transmits waveforms such as with different data rates. These transmissions are modulated (e.g. phase modulated) onto quadrature channels of a common carrier, and are then combined. The resulting composite modulated waveform is upconverted to RF, power amplified, split and routed to separate ports for transmission. The transmitted signals are then received, downconverted and demodulated to produce the original signals. |
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DETAILED DESCRIPTION Accordingly, an object of the present invention is to eliminate the need for separate modulation (and other operations if needed) for each transmission.
Another object of the present invention is to eliminate the need for separate modulation, separate upconversion to RF frequency, and separate power amplification for each transmission.
Further objects of the present invention are to provide significant size, weight and cost reductions due to elimination of all but one chain of modulation, up conversion and power amplification.
Still another object of the present invention is to provide apparatus and method for simultaneous transmission and reception of multiple signals on a single channel.
Yet another object of the present invention is to eliminate the need for separate demodulation (and other operations if needed) for each reception.
A further object of the present invention is to eliminate the need for separate demodulation and separate downconversion from RF frequency for each reception.
Still other objects of the present invention are to provide significant size, weight and cost reductions due to elimination of all but one chain of demodulation and downconversion.
Briefly, these and other objects of the present invention are accomplished by a transmitter which simultaneously transmits waveforms such as with different data rates.
These transmissions are modulated (e.
g.
phase modulated) onto quadrature channels of a common carrier.
The composite modulated waveform is upconverted to RF, power amplified, split and routed to separate ports for transmission.
The transmitted signals are then received, downconverted and demodulated to produce the original signals.
Although more than one chain of downconverter and demodulator can be utilized for this purpose, each such chain is nonetheless capable of producing each of the originally transmitted signals.
For example, a single transmitter could transmit both higher and lower rate data waveforms in which the higher rate transmission requires directional antenna transmission to a selected receiver and the lower data rate channel requires omnidirectional antenna coverage for a plurality of receivers (including the selected receiver)
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Fault Detection 
