diff --git a/Courses/EE2T1_Telecommunication_and_Sensing.typ b/Courses/EE2T1_Telecommunication_and_Sensing.typ new file mode 100644 index 0000000..f201ba8 --- /dev/null +++ b/Courses/EE2T1_Telecommunication_and_Sensing.typ @@ -0,0 +1,116 @@ +#import "../template/lib.typ": * +#set page(paper: "a4") +#show: notes.with( + title: [EE2T1], + subtitle: [Telecommunication and Sensing], + author: "Folkert Kevelam" +) + += Lecture 1 - Introduction + +== Information + +#definition[ + Information content: + + Information is related to probability: a less probable message contains + more information + + $ + I_j = log_2(1/P_j) = - log_2(P_j) space "[bit]" + $ + + Information is additive: + + $ + I_(i j) &= log_2(1/(P_i P_J)) = -log_2(P_i)-log_2(P_j) \ + &= I_i + I_j + $ + + iff the messages are independent. +] + +#definition[ + Source entropy, the average amount of information per message generated + by a source: + + $ + H = sum_(j=1)^M P_j I_j = sum_(j=1)^M P_j log_2(1/P_j) space "[bit/symbol]" + $ + + In a binary system, the maximum source entropy will be when $P_1 = P_0 = 0.5$. + The speed of a source: + + $ + R = H/T space "[bit/s]" + $ +] + +#theorem[ + Shannon-Hartley theorem: + + $ + C = B dot log_2( 1 + S/N) space "[bit/s]" + $ + + - $C = "capacity [bit/s]"$ + - $B = "bandwidth [Hz]"$ + - $S/N = "ratio of signal power to the noise power"$ +] + +== Principles of range measurement + +#definition[ + The transmitter "fires" a signal and the receiver measures the time delay + $tau$ between the moments of transmission and reception of the echo. + + $ + 2R = c dot tau arrow R = (c dot tau) / 2 + $ + + with $c$ being the speed of light. +] + +#definition[ + The ability of a radar to resolve two targets with a range difference + $delta R$ is called *range resolution*. + + $ + delta R = (c dot tau_p) / 2 approx c/(2 B) space "[m]" + $ +] + +== Modulation + +#definition[ + Modulation: *manipulation of a signal waveform* to carry information, in + order to transmit the signal at a specified frequency in the spectrum. + + $ + s(t) = R(t)cos(2 pi f_c t + phi(t)) + $ + + with + + $ + R(t) = L{m(t)} space "linear modulation" \ + phi(t) = L{m(t)} space "angle modulation" + $ +] + +== Practical signal waveforms + ++ DC-value, mean value: $ w_(D C) = = lim_(T arrow infinity) 1/T integral_(-T/2)^(T/2) w(t) d t $ ++ Instantaneous power: $ p(t) = v(t) dot i(t) $ ++ Average power: $ P= = $ ++ RMS-value: root-mean-square: $ w_(r m s) = sqrt() $ + For a resistive load: $ P = v_(r m s) i_(r m s) = ()/R = R $ ++ Normalized power = power delivered to a $1 omega$ load. + $ P = = lim_(T arrow infinity) 1/T integral_(-T/2)^(T/2) w^2(t) d t space "[W] = [J/s]" $ + $w(t)$ is a *power waveform* iff $0 < P < infinity$. ++ Normalized energy = energy dissipated in a $1 omega$ load. + $ E = lim_(T arrow infinity) integral_(-T/2)^(T/2) w^2(t) d t space "[J]" $ + $w(t)$ is an *energy waveform* iff $0 < E < infinity$. + +A signal waveform $w(t)$ cannot both be an *energy waveform* and a *power waveform*. +Practical waveforms are always energy waveforms.