uantizing noise should be reduced at signal level -40 dBm0 and how much longer sam- ple words would be required for this.) Problem 3.12 How much PCM voice or stereo music (assume that CD-quality music requires 700 Kbps for both channels) can be stored in (a) a 1.44-MB (B = byte = 8 bits) disc and (b) a 20-GB memory space of a hard disk? Problem 3.13 Explain how (a) DPCM and (b) ADPCM reduce data rates compared to ordinary PCM. Introduction to Telecommunications Network Engineering Problem 3.14 Explain the basic principle of GSM speech coding. Problem 3.15 The input power of an amplifier is 2 mW and output power is 1W. What are the power levels (dBm) at the input and output and what is the gain of the amplifier in decibels? Problem 3.16 The input and output powers of a circuit are in listed in Table 3.3. What is the absolute attenuation L, absolute gain g attenuation in decibels, gain in decibels, and output power level for each case (a-e)? Problem 3.17 What is the power in watts that corresponds to power levels of (a) 0 dBm, (b) 3 dBm, (c) -3 dBm, (d) 10 dBm, (e) 20 dBm, (f) 100 dBm, and (g) -100 Problem 3.18 Figure 3.24 illustrates a telecommunications connection using a geostation- ary satellite. Calculate the input and output powers of the satellite amplifier and output power of the antenna at the receiving Earth station. Define both power levels in dBm and absolute power in watts. Use decibels and derive power levels, in dBm values, first. Problem 3.19 The input power of a 40-km cable system is 2W (power at the beginning of the cable). An amplifier with a 64-dB gain is installed 24 km from the Table 3.3 Input and Output Powers of a Circuit (a) 1 mW (b) 1 mW 0.5 mW (c) 1 mW (d) 10 mW 10 mW Signals Carried over the Network Gain of the satellite: g = 80 dB Gain of the antenna: g = 30 dB Uplink attenuation: g = 30 dB Downlink L = 200 dB L = 200 dB g = 50 dB Transmitting Earth station g = 70 dB Receiving P = 100W Earth station P = ? Figure 3.24 Satellite transmission link. input. Define the signal power level, dBm