Problem on multi level TDM

Question

Ten sources, six with a bit rate of 200 Kbps and four with a bit rate of 400Kbps are to be combined using multi level TDM  with no sync bits. Answer the questions below about the final phase of multiplexing:

a. Find out the size of a frame in bits?

b. Find out the frame rate?

c. Evaluate the duration of a frame?

d. Determine the data rate?

Answer 1

Combine six 200-kbps sources into three 400-kbps. So there are seven 400-kbps channels.

a. All output frames carry 1 bit from each of the seven 400-kbps line. Frame size = 7 × 1 = 7 bits.

b. All frame carry 1 bit from each 400-kbps source. Frame rate = 400,000 frames/s.

c. Frame duration = 1 /(frame rate) = 1 /400,000 = 2.5 μs.

d. Output data rate = (400,000 frames/s) × (7 bits/frame) = 2.8 Mbps.