 Wideband FM modulator and AFC control loop therefor |
| The present invention pertains to an improved digital frequency discriminator for use in a wideband ... |
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| Extremely accurate automatic frequency control circuit and method therefor |
| The above and other objects are achieved by an automatic frequency control circuit which receives ... |
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| Receiver data gate with automatic gain control |
| OF THE PREFERRED EMBODIMENT Referring to the Figure, a telephone system, such as a private branch ... |
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| Picture transmission system using secondary differential variable sampling rate coding |
| Accordingly, the principal object of the present invention is to provide a picture transmission ... |
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| Recorder actuator for communication lines |
| What is claimed is: 1. An adapter circuit to connect a tape recorder to the input line of a ... |
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| High speed on-chip clock phase generating system |
| It is the principal object of the present invention to provide a novel clock system for a ... |
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| Phase-locked loop circuit and method |
| OF THE INVENTION Referring now to the drawings, FIG. 1 shows a block diagram of a first embodiment ... |
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| Data recovery apparatus and methods |
| The present invention has been made in view of the above circumstances and has as an object to ... |
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| Multiplexing digital communication system |
| OF A PREFERRED EMBODIMENT FIG. 1 shows system components that can be incorporated into a broadband ... |
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Nonterrestrial cellular mobile telecommunication network
| Details |
Inventors: Ray, J. C.; George, Robert L.; Hoppe, Geoffrey A.; Jones, Stephen S.; McKenna, Daniel B.;
Assignee: Aircell Incorporated (Boulder, CO)
Primary Examiner: Chin; Wellington
Assistant Examiner: Nguyen; Lee
Attorney, Agent or Firm: Duft, Graziano & Forest, P.C.
The multidimensional cellular mobile telecommunication system extends the usage of existing cellular mobile telecommunication radio frequencies allocated for ground-based communications to non-terrestrial mobile subscriber stations by adding an overlay of non-terrestrial cells of predetermined geometry and locus in space to the existing ground-based cellular cell site network. The polarization of the signals produced by the non-terrestrial antenna elements is a polarization that is different than and preferably substantially orthogonal to the polarization of the cellular radio signals produced by the ground-based antennas, such as a horizontal polarization, to thereby minimize the possibility of interference with the vertically polarized ground-based radio signals. Furthermore, the control signals exchanged between the non-terrestrial mobile subscriber stations and the non-terrestrial cell site controller are architected to avoid the possibility of interference with ground-based cell site transmitter-receiver pairs. In particular, the control channels used for the non-terrestrial mobile subscriber stations are selected such that the control signals transmitted in these channels are unrecognizable to the ground-based mobile subscriber stations and cell site transmitter-receiver pairs, so that even if broadcasts from a non-terrestrial mobile subscriber station reach a ground-based mobile subscriber station or cell site receiver, they cannot be interpreted and are rejected out of hand. |
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DETAILED DESCRIPTION The multidimensional cellular mobile telecommunication system of the present invention extends the usage of existing cellular mobile telecommunication radio frequencies allocated for ground-based communications to non-terrestrial mobile subscriber stations in a manner that avoids the possibility of signal interference between the ground-based and non-terrestrial mobile subscriber stations.
In particular, the multidimensional cellular mobile telecommunication system adds an overlay of non-terrestrial cells of predetermined geometry and locus in space to the existing ground-based cellular mobile telecommunication network.
The polarization of the cellular radio signals produced by the non-terrestrial antenna elements is a polarization that is different than and preferably substantially orthogonal to the polarization of the cellular radio signals produced by the ground-based antennas, such as a horizontal polarization, to thereby minimize the possibility of interference with the nominally vertically polarized ground-based cellular radio signals.
Furthermore, the control signals exchanged between the non-terrestrial mobile subscriber stations and the non-terrestrial cell site controller are architected to avoid the possibility of interference with ground-based cell site transmitter-receiver pairs.
In particular, the control channels used for the non-terrestrial mobile subscriber stations are selected such that the control signals transmitted in these channels are unrecognizable to the ground-based mobile subscriber stations and cell site transmitter-receiver pairs, so that even if broadcasts from a non-terrestrial mobile subscriber station reach a ground-based mobile subscriber station or cell site receiver, they cannot be interpreted and are rejected out of hand.
Architecture of a Cellular Mobile Telecommunication System FIG.
1 illustrates a typical prior art ground-based cellular mobile telecommunication system which includes a plurality of mobile telephone switching offices (MTSO) 102, 103, each of which is connected via communication facilities 1121-1124, 1131-1133 to a plurality of cell site transmitter-receiver pairs 121-124, 131-133 (also termed base stations herein)
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Multiplexer-related 
