System and method for enhancing the performance of wideband digital RF transport systems

• US 20070238457A1
• Filed: 04/06/2006
• Published: 10/11/2007
• Est. Priority Date: 04/06/2006
• Status: Active Grant

• Current Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Original Assignee: ADC Telecommunications Incorporated (TE Connectivity Limited)
• Inventors: Wala, Philip
• Granted Patent: US 7,610,046 B2
• Time in Patent Office: Days
• US Class Current: 455/424
• CPC Class Codes: H04J 3/1629 Format building algorithm
• CPC Class Codes: H04J 3/1647 Subrate or multislot multiplexing

Abstract

A system and method for enhancing the performance of wideband digital RF transport systems is disclosed, which enables the transport of different bandwidth segments on a plurality of wideband channels by selecting an optimal clock sample rate for each bandwidth segment to be transported. Thus, the bandwidth segments are proportionally allocated so that an optimum amount of bandwidth can be transported at the serial bit rate. As one example, a system for enhancing the performance of a wideband digital RF transport system is disclosed, which includes a transmit unit, a receive unit, and an optical transmission medium connected between the transmit unit and the receive unit. The transmit unit includes a plurality of wideband RF analog signal inputs coupled to a plurality of analog-to-digital, digital down-converter (A/D DDC) devices. Notably, the sample rate of each A/D DDC device is determined by a respective sample clock. The digitized wideband RF segments at the outputs of the A/D DDC devices are combined and converted to a frame structure, converted to serial form, and transmitted on the optical transmission medium to the receive unit. A light detector device in the receive unit detects the serial bit stream on the optical transmission medium, the serialized frames are converted back to the original frame format, and the original digitized wideband RF segments are reconstructed. Each digitized wideband RF segment is coupled to a respective D/A digital up-converter (D/A DUC) device associated with a particular wideband RF signal input on the transmit side. Notably, the output sample rate of each D/A DUC device is determined by a respective sample clock, which provides the same sample rate as that of the associated A/D DDC device in the transmit unit. The sample rate of each A/D DDC device (and associated D/A DUC device) is pre-selected so that the transmission medium can transport the optimum amount of RF bandwidth at the given serial bit rate.

Claims

1. A system for enhancing the performance of a wideband digital RF transport system, comprising:

a plurality of bandwidth input interface devices; and

a plurality of sample rate devices coupled to said plurality of bandwidth input interface devices, each sample rate device of said plurality of sample rate devices adapted to set an input sample rate of an associated bandwidth input interface device.

2. The system of claim 1, further comprising:

a mapper/framer device, an output of each bandwidth input interface device coupled to an input of said mapper/framer device;

a serializer device coupled to an output of said mapper/framer device;

a transmit device coupled to an output of said serializer device; and

a transmission medium coupled to an output of said transmit device.

3. The system of claim 1, wherein said plurality of bandwidth input interface devices comprises a plurality of analog-to-digital digital down-converters.

4. The system of claim 1, wherein said plurality of sample rate devices comprises a plurality of sample clocks.

5. The system of claim 2, wherein said transmit device comprises a laser transmitter device, and said transmission medium comprises a fiber optic cable.

6. The system of claim 2, further comprising:

a digital signal detection device coupled to said transmission medium;

a deserializer device coupled to an output of said digital signal detection device;

a demapper/deframer device coupled to an output of said deserializer device;

a plurality of output interface devices, an input of each output interface device of said plurality of output interface devices coupled to a respective output of said demapper/deframer device; and

a plurality of sample clock devices, each sample clock device adapted to set an output sample rate of an associated output interface device of said plurality of output interface devices.

7. A system for enhancing the performance of a wideband digital RF transport system, comprising:

means for inputting a plurality of bandwidths;

means for setting a plurality of input sample rates coupled to said means for inputting said plurality of bandwidths;

means for combining said plurality of bandwidths;

means for constructing at least one frame including said combined plurality of bandwidths;

means for converting said at least one frame to a serial form;

means for generating a signal including said at least one frame in serial form;

means for transporting said signal, coupled to an output of said means for generating;

means for detecting said at least one frame from said signal, coupled to said means for transporting;

means for converting said detected at least one frame to a parallel form;

means for deconstructing said at least one frame to produce said combined plurality of bandwidths;

means for separating said combined plurality of bandwidths;

means for converting said plurality of bandwidths to a second plurality of bandwidths; and

means for setting an output sample rate for each bandwidth of said second plurality of bandwidths.

8. The system of claim 7, wherein said means for inputting a plurality of bandwidths comprises a plurality of analog-to-digital digital down-converters, and said means for setting a plurality of input sample rates comprises a plurality of sample clocks.

9. The system of claim 7, wherein said means for combining said plurality of bandwidths comprises a mapper device.

10. The system of claim 7, wherein said means for generating a signal comprises a millimeter wave radio transmitter device.

11. The system of claim 7, wherein said means for generating a signal comprises a wireless transmitter device.

12. The system of claim 7, wherein said means for generating a signal comprises a laser transmitter device.

13. The system of claim 7, wherein said means for transporting said signal comprises a fiber optic cable.

14. The system of claim 7, wherein said means for detecting said at least one frame from said signal comprises a photo-detector device.

15. The system of claim 7, wherein said means for converting said plurality of bandwidths to a second plurality of bandwidths comprises a plurality of digital-to-analog digital up-converter devices, and said means for setting an output sample rate for each bandwidth of said plurality of bandwidths comprises a plurality of sample clocks.

16. A method for enhancing the performance of a wideband digital RF transport system, comprising the steps of:

inputting a plurality of bandwidths; and

setting a unique input sample rate for each bandwidth of said plurality of input bandwidths;

combining said plurality of bandwidths;

converting said combined plurality of bandwidths to at least one frame structure;

converting said at least one frame structure to a serial form;

converting said at least one frame structure in serial form to a plurality of coded signals; and

transporting said plurality of coded signals on a transmission medium.

17. The method of claim 16, further comprising the steps of:

detecting said at least one frame from said plurality of coded signals;

converting said detected at least one frame to a parallel form;

deconstructing said at least one frame to produce said combined plurality of bandwidths;

separating said combined plurality of bandwidths;

converting said plurality of bandwidths to a second plurality of bandwidths; and

setting an output sample rate for each bandwidth of said second plurality of bandwidths.

18. The method of claim 16, wherein the inputting step is performed by a plurality of input interface devices, and the setting step is performed by a first plurality of sample clock devices.

19. The method of claim 17, wherein the step of converting said plurality of bandwidths to a second plurality of bandwidths is performed by a plurality of output interface devices.

20. The method of claim 17, wherein the step of setting an output sample rate is performed by a second plurality of sample clock devices.