Multi-channel optical communication

1. An optical fiber communications apparatus comprising:

a housing provided with a motherboard and with a support defining a plurality of card receptors;

a plurality of modular cards, each of which is engageable with the motherboard via one of the card receptors;

an optical card comprising a first of said modular cards, said optical card including an optical transceiver for communication, using a digital optical communications signal, over a single optical fiber link, wherein

each modular card being provided with a plurality of circuit sub-assemblies, each circuit sub-assembly being configured for digital communication with a respective local audio, video or data electronic device via a respective connector using a respective electronic information-carrying signal, and wherein

each circuit sub-assembly being configured for communication of an audio, video or data information-carrying signal with the optical transceiver using the digital optical communications signal; and

circuitry for assigning time periods for the individual information-carrying signals of the circuit sub-assemblies controlling transmission of communications between the optical transceiver and the circuit sub-assemblies, and time division multiplexing said communications over the single optical fiber link to communicate a predetermined combination of audio, video and data channels multiplexed onto a single optical channel carried by the optical fiber link.

2. Apparatus as claimed in claim 1 wherein said circuitry is configured to assign a time period to the information carrying signal of a corresponding circuit sub-assembly according to a maximum bandwidth of the corresponding circuit sub-assembly.

3. Apparatus as claimed in claim 2 wherein each modular card is adapted to determine whether a successive card is engaged with a bus and, if so, to inform the successive card, said successive card being adapted to add itself to a daisy chain.

4. Apparatus as claimed in claim 3 wherein said successive card only adds itself to the daisy chain if there is sufficient available bandwidth.

5. Apparatus as claimed in claim 1 wherein said optical transceiver operates at a channel bandwidth and each of said circuit sub-assemblies operates at corresponding sub-assembly bandwidths; wherein an available bandwidth comprises the channel bandwidth less the sum of the sub-assembly bandwidths of all of the circuit sub-assemblies of the daisy chain and wherein said successive card is adapted to add the circuit sub-assemblies of said successive card to the daisy chain only if the available bandwidth is equal to or greater than the combined sub-assembly bandwidths of the circuit sub-assemblies of said successive card.

6. Apparatus as claimed in claim 1 , wherein the optical transceiver is such as to communicate using a digital optical communications signal operating in a first common communications protocol over the single optical fiber.

7. Apparatus as claimed in claim 1 , wherein each circuit sub-assembly is such as to communicate with its respective electronic device using a second protocol which is an audio protocol, a video protocol or a data protocol.

8. Apparatus as claimed in claim 7 wherein the second protocol corresponds to data communicated by satellite.

9. Apparatus as claimed in claim 1 , wherein the circuitry for assigning time periods is provided on the optical card.

10. Apparatus as claimed in claim 1 , further comprising firmware on each circuit sub-assembly, the firmware on a given circuit sub-assembly controlling communications with the respective local electronic device.

11. Apparatus as claimed in claim 1 wherein each modular card comprises a plurality of sockets, each socket being adapted to receive a corresponding circuit sub-assembly.

12. Apparatus as claimed in claim 11 wherein any circuit sub-assembly is received by a corresponding socket of a modular card so that each circuit sub-assembly is removably pluggable.

13. Apparatus as claimed in claim 1 wherein any one of said modular cards is configurable according to the circuit sub-assemblies provided therewith.

14. Apparatus as claimed in claim 1 , wherein each circuit sub-assembly is an FPGA mounted on an FPGA receiver associated with the respective modular card.

15. Apparatus as claimed in claim 1 , wherein the digital, optical communications signal is an Ethernet protocol signal.

16. Apparatus as claimed in claim 1 , wherein each information-carrying signal is any one of a group of video, audio, and data protocols including composite video, SDI, HDSDI, DVD-ASI, S-Video, VGA, DVI, and HDMI, analogue audio, studio quality audio, digital AES/EBU audio, RS-232, RS-422, RS-485, dry contact, 10/100 Ethernet, and gigabit Ethernet.

17. An optical fiber communications system comprising: a first optical fiber communications apparatus and a second optical fiber communications apparatus, each of which is as claimed in claim 1 ; and a single optical fiber link connecting the two optical fiber communications apparatuses for communication using a digital optical communications signal.

18. A system as claimed in claim 17 , wherein each optical fiber communications apparatus has the same number of modular cards, the modular cards in the first optical fiber communications apparatus being arranged to mirror the configuration of the modular cards in the second optical fiber communications apparatus, and the circuit sub-assemblies provided in the first optical fiber communications apparatus being arranged so as to mirror the circuit sub-assemblies in the second optical fiber communications apparatus.

19. An optical fiber communications apparatus comprising:

a housing including a motherboard;

a plurality of modular cards, each of which is configurable as an optical card or as an electronic data card engageable with the motherboard;

an optical card including an optical transceiver for communication over a single optical fiber link using a digital optical communications signal, wherein

each modular card includes a plurality of circuit sub-assemblies, each circuit sub-assembly being configured for digital communication with a respective local audio, video or data electronic device via a respective connector using a respective electronic information-carrying signal, wherein

each circuit sub-assembly being configured in a daisy chain for communication of an audio, video or data information-carrying signal with the optical transceiver using the digital optical communications signal; and

circuitry for time division multiplexing communications between the optical transceiver and the circuit sub-assemblies over the single optical fiber link to communicate a combination of audio, video and data channels multiplexed onto a single optical channel carried by the optical fiber link, wherein

each modular card is configured to compare an available bandwidth against its own bandwidth and when said own bandwidth is less than said available bandwidth, to add its circuit sub-assembly to the daisy chain.

20. Apparatus as claimed in claim 19 , wherein each circuit sub-assembly is such as to communicate with its respective electronic device using a second protocol which is an audio protocol, a video protocol or a data protocol, wherein the second protocol corresponds to data communicated by satellite.