# Category: Uncategorized #### 1) A data stream needs to be transmitted and m=4 pulse levels are used (4-ray transmission). to reduce ISI. a raised-cosine pulse p(t) shown in the figure bellow, is used

... #### 7.3-5 A pulse p(t) is shown in Fig. P7. 3-5 satisfies Nyquist criterion. If f1 = 0.8 MHz and f2 = 1.2 MHz determine the maximum rate at which binary data can be transmitted by this pulse using Nyquist criterion. What is the roll-off factor?

... #### 7.3-3 A leased telephone line of bandwidth 3 KHz is used to transmit binary data. Calculate the data rate (in bits per second) that can be transmitted if we use:

... #### 7.2-3 Derive the PSD for a binary signal using differential code with half-width rectangular pulses Determine the PSD S,(w).

... #### 2. A signal band limited to 1 MHz is sampled at a rate 50 percent higher than the Nyquist rate, and quantized by u-law quantizer with u=255. When a u-law compander is used , the output signal-to- quantizing noise (SNR) of the quantizer is approximately as follows:

... #### 6.2-10 The output SNR of a 10-bit PCM (n= 10) was found to be 30 dB. The desired SNR to the desired value by increasing the number of quantized levels L. Find the fractional increase in the transmission bandwidth requited for this increase in L.

... #### 7.5 A signal band-limited to 4.2 MHz is sampled at a rate 25% higher than the Nyquist rate and quantized into 256 levels using a u-law quantizer with u=255.

... #### 5.2-8 A signal band limited to 1 MHz is sampled at a rate 30% above the Nyquist rate and quantized into 256 levels using a law quantizer with u=255

... #### A signal band limited to 1 MHz is sampled at a rate 50% higher than the Nyquist rate and quantized into 256 levels. (a) Determine the signal-to-quantization-noise ratio. (b) The SNR (the received signal quality) found in part (a) was unsatisfactory. It must be increased at least by 10 dB. Would you be able to obtain the desired SNR without increasing the transmission bandwidth. If it was found that a sampling rate 20% above the Nyquist rate is adequate? If so, explain how. What is the maximum SNR that can be realized in this way?

... #### 6.2-3 and 6.2-6 A sinusoidal signal m/h with frequency f=4.5 MHz is transmitted by binary pulse code modulation system, It the signal to quantization noise ratio is require to least 58 dB, determine the minimum signal to quantization noise ratio.

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