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Regarding digital transmission of multimedia traffic, complete the following:

In PAM encoding, the general rule is that we need to sample at twice the bandwidth. In addition, if we use n bits for each sample, we can represent 2ⁿ loudness (amplitude) levels. What transmission speed would you need if you wanted to encode and transmit, in real time and without compression, two-channel music with a bandwidth of 22kHz and 1000 loudness levels?
Note: The sampling size, in bits, must be an integer. To minimize quantizing errors, it is customary to select a sampling rate that is twice as much as the signal bandwidth.

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Final answer:

To encode and transmit high-fidelity two-channel music with 1000 loudness levels and 22kHz bandwidth, 10 bits per sample are necessary. Sampling at a rate of 44kHz per channel, the total transmission speed required is 1.76 Mbps.

Step-by-step explanation:

The question involves calculating the required transmission speed for encoding and transmitting high-fidelity two-channel music. To determine the transmission speed, we must consider both the sampling rate and the bit depth required to encode the audio. Since the music has a bandwidth of 22kHz, the sampling rate must be at least twice this value according to the Nyquist theorem, which is 44kHz per channel. To minimize quantizing errors, we choose a sampling rate that is twice the bandwidth, hence we use a sampling rate of 44kHz.

To represent 1000 loudness levels, we need to determine the number of bits required per sample. 1000 levels can be approximated as 2³10, since 2³9 is 512 and 2³10 is 1024, and we need an integer number of bits. Therefore, we need 10 bits per sample.

Finally, to calculate the transmission speed, we use the formula:

  • Transmission speed = Sampling rate × number of bits per sample × number of channels
  • Transmission speed = 44,000 samples/s × 10 bits/sample × 2 channels
  • Transmission speed = 880,000 bits/s or 880 Kbps per channel

Therefore, the total transmission speed required for a two-channel music audio is 1.76 Mbps (880 Kbps × 2).

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