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Multiplex Name: BBC A BBC B HD SD or HD: SD HD Channel Centre Frequency: 674MHz (Ch 46) 626 MHz (Ch 40) Nominal Channel
Posted: Wed Apr 27, 2022 5:54 pm
by answerhappygod
- Multiplex Name Bbc A Bbc B Hd Sd Or Hd Sd Hd Channel Centre Frequency 674mhz Ch 46 626 Mhz Ch 40 Nominal Channel 1 (86.9 KiB) Viewed 37 times
Multiplex Name: BBC A BBC B HD SD or HD: SD HD Channel Centre Frequency: 674MHz (Ch 46) 626 MHz (Ch 40) Nominal Channel Bandwidth: 8 MHz 8 MHz Modulation Scheme: 64 QAM 256 QAM Transmit Power (ERP) 100 kW 100 kW Table Q14a: Selected information for the Black Hill TV transmitter serving Central Scotland. a) Explain, with the aid of a constellation diagram, what the term 256 QAM' means. 2 Marks b) For the BBC B HD transmission, what is the theoretical maximum data rate (in bitos ) that may be supported without causing inter- symbol interference, assuming that the full nominal channel bandwidth is used? 2 Marks c) If the actual net transmitted data rate for BBC BHD is two thirds of the theoretical maximum ISI-free rate calculated in Part (ii), calculate the spectral efficiency of the transmission, in bit.Hz1. 2 Marks