Multiplexer for Digital Broadcasting

Please furnish me with the design and performance limitations for the following specifications of a Digital MUX for multiplexing Audio, Video and Data:

• Maximum number of channels: What are the effects of INCREASED numbers of the channels of a MUX Vs performance or quality (compare the performance of say a MUX with 20 and with 2 muxes of 10 channels each.
• Maximum Data Rate
• Optical Output
• Wavelengh
• Operating Voltage: AC Vs DC. Which is better and why.
• Data Interface: Which is best and why.
• Operating temperature: maximum/minimum limitations
• Operating humidity: maximum/minimum limitations

Why is the TDM MUX said to have the following advantages:

· Low cost equipment

· Low and constant delay

· Ease of installation and maintenance

· Unsurpassed standards-based

· Multi-vendor capabilities

I have an assignment from my employer to investigate and suggest a digital MUX for a Pilot Project for Digital Broadcasting to be introduced in my country. Please assist.