1. ECE 442 C OMMUNICATION S YSTEM D ESIGN L ECTURE 1. M ODULATION Husheng Li Dept. of EECS The University of Tennessee

2. C OURSE I NFORMATION Lecturer: Husheng Li Time: 12:40pm --- 1:55pm Location: MK404 Office time: 3pm --- 4pm, everyday Office: MK644 Course website http://web.eecs.utk.edu/~husheng/ECE442_2012.htm

3. T EXTBOOK A. B. Carlson and P. B. Crilly, Communication Systems, 5 th edition, McGraw Hill, 2010

4. R EFERENCE B OOK (1) J.Proakis and M. Salehi, Digital Communications, 5 th Edition, McGraw Hill, 2008

5. R EFERENCE B OOK (2) A. Goldsmith, Wireless Communications, Cambridge, 2005

6. R EFERENCE B OOK (3) D. Tse and P. Viswanath, Fundamentals of Wireless Communication, Cambridge, 2005

7. L OGISTICS Grading: midterm/final tests (50%), homework (4 problems each week, 25%), projects (totally 3, 25%) Projects: Project 1: Use Matlab Simulink to simulate the performance of a communication system (deadline: midterm) Project 2: Use Matlab to implement the coding and decoding algorithms of convoulutional codes. Evaluate the performance (deadline: April 15th). Project 3: A report about 4G systems (deadline: Final exam)

8. C OVERAGE

9. D IGITAL M ODULATION / D EMODULATION Modulation means loading digital information bits into the continuous waveforms at the transmitter. Demodulation is the inverse procedure. When a sinusoidal signal is used for radio emission, the information can be carried at the three elements: amplitude (amplitude-shift keying: ASK), frequency (frequency-shift keying: FSK) and phase (phase-shift keying: PSK).

10. I LLUSTRATION

11. B ANDPASS S IGNAL Any modulated bandpass signal can be writtend in the following quadratic-carrier form: The equivalent lowpass spectrum is defined as

12. A MPLITUDE M ODULATION An M-ary ASK signal can be written as A special case is called OOK.

13. S PECTRUM E FFICIENCY The spectrum efficiency is given by

14. QAM Quadrature-carrier AM (QAM) achieves twice the spectrum efficiency of binary ASK Signal Constellation

15. P HASE M ODULATION An M-ary PSK signal is expressed in general by which can be decomposed into the quadrature form. QPSK8-PSK

16. F REQUENCY M ODULATION In FSK, the frequency is given by

17. S PECTRUM OF FSK The i and q elements of Sunde’s FSK are mutually independent. Sunde’s FSK has very little spillover.

18. M- ARY O RTHOGONAL FSK AND CPFSK For the M-ary orthogonal FSK, the M keyed frequencies are spaced by In CPFSK, the information signal is the RF signal is then given by

19. C OHERENT B INARY S YSTEMS A coherent bandpass system employs information about the carrier frequency and phase at the receiver to detect the message. A noncoherent system does not need synchronization with the carrier phase, thus causing performance degradation compared with coherent bandpass system.

20. B ANDPASS B INARY R ECEIVER The filter for optimum binary detection should be matched to the difference between the two signaling waveforms.

21. T WO A LTERNATIVE A PPROACHES Parallel matched filter Correlation detector

22. H OW TO A NALYZE THE B IT E RROR R ATE ? When the two possible outputs are z1 and z0, the bit error rate is given by