The stair-case approximated output is given to the LPF. The amplifier gain determines the step-size and both are proportional. The instant of time when the eye opening is wide, will be the preferred time for sampling. Fig.1 Block diagram of Communication system. Following are the parameters of such code. Following is the diagram of DPCM Receiver. This is frequency hopping technique, where the users are made to change the frequencies of usage, from one to another in a specified time interval, hence called as frequency hopping. Microwave and Digital communication Lab 4 PCM Operation (with DC input) Modulation: 8. Transmitter. Block Diagram of Communication System Main building blocks of the communication system in electronics are-*Source of information *Input transducer *Transmitter *Channel *Receiver *Destination All these basic building blocks of communication system are shown in the block diagram below-Block Diagram of Communication System Block diagram of television transmitter. Following is the block diagram for the same. PSK technique is widely used for wireless LANs, bio-metric, contactless operations, along with RFID and Bluetooth communications. For this, the value $L_{min}$ has to be determined. The Equalizer is feasible to get implemented. It is responsible for the generation of information that is to be transmitted. Hence, these techniques are used for military purposes. The following figures represent the two types of uniform quantization. Here we will discuss, What is Amplitude Modulation and various Amplitude Modulation Techniques. Any modulated signal has a high frequency carrier. The PSKQ signal is anyhow phase shifted by 90° before being modulated. Digital technology stores and transmits data in the form of 1s and 0s. When we observe the possibilities of the occurrence of an event, how surprising or uncertain it would be, it means that we are trying to have an idea on the average content of the information from the source of the event. This binary or digital information has many types and forms, which are discussed further. The rate at which data can be communicated is called the data rate. The following figures represent MUX and DEMUX. Example − Optical fiber communications use WDM technique to merge different wavelengths into a single light for communication. Actual eye patterns are used to estimate the bit error rate and the signal-to-noise ratio. Set DC source to some value say 1 V with the help of multimeter and connect it to the A/D converter input and observe the output LED’s. The following figure quotes an example for blocks of data and stream of data, used for transmission of information. The following figure illustrates an example for a quantization error, indicating the difference between the original signal and the quantized signal. The ratio k/n is the code rate. The signal droop is caused at the places where signal is non-zero at 0 Hz. The basic idea of correlative coding is achieved by considering an example of Duo-binary Signaling. Parity bits help in error detection and error correction, and also in locating the data. The output of a PCM will resemble a binary sequence. • Source Encoder The signal produced by source is converted into digital signal consists of 1′s and 0′s. A PCM wave, after transmitting through a channel, gets distorted due to the noise introduced by the channel. Block Diagram of Basic Communication System: Fig. An intruder with no official access is never allowed to crack them. In an Analog receiver, the figure of merit at the detection process can be termed as the ratio of output SNR to the input SNR. Hence, a separate clock line needs to be provided. M represents a digit that corresponds to the number of conditions, levels, or combinations possible for a given number of binary variables. The width of the eye opening defines the time interval over which the received wave can be sampled without error from ISI. These are few of the techniques used in digital communications. FIGURE 1.1-1 Basic elements of a digital communication system. It is denoted by r and the value of r is r < 1. The decision device decides its output based on whether the amplitude of the quantized pulse and the noise, exceeds a pre-determined value or not. This is called as Channel coding theorem. Digital data to Digital signals − These are in this section. Following are the advantages of spread spectrum −. The transmitter performs the sampling, quantizing and encoding of the signal. Block diagram of television transmitter. We further designate digital systems as being binary systems if only two possible symbols exist, and M-ary systems otherwise, where M is the number of possible alternative symbols. Very easy design of the modulator and the demodulator, Slope Over load distortion (when Δ is small). ASSIGNEMENT SET # 1 Spring 20182019B 3 EE LE 290:DIGITAL SYSTEMS Feb 8, 2018 1. Signal processing functions such as encryption and compression are employed in digital circuits to maintain the secrecy of the information. The signals are separated by $\frac{1}{2T_s}$ The spectral envelope is represented in a compressed form, using the information of the linear predictive model. Such a signal is represented as $x(f) = 0 \: for \: \mid f \mid > W$. This is an encoding technique which has three voltage levels namely +, - and 0. Components and Basic Block Diagram of Data Communication. If the above example is considered, as there is a long sequence of constant voltage level and the clock synchronization may be lost due to the absence of bit interval, it becomes difficult for the receiver to differentiate between 0 and 1. Inverse Mapping the channel output sequence into an output data sequence. This is also called as 2-phase PSK or Phase Reversal Keying. NRZ Codes has 1 for High voltage level and 0 for Low voltage level. The information is replaced without any loss. The following figure indicates the difference between analog and digital signals. This is the last block which converts the signal into the original physical form, which was at the input of the transmitter. The step-size error that may occur at the transmitter is called granular noise, which is eliminated here. Hz making the signals orthogonal to each other. The mapping is done by the transmitter, with the help of an encoder, whereas the inverse mapping is done by the decoder in the receiver. Block diagram of a simple Digital Communication System. FSK is a scheme of frequency modulation. Now, we will discuss the functioning of … The transmitter section of a Pulse Code Modulator circuit consists of Sampling, Quantizing and Encoding, which are performed in the analog-to-digital converter section. A-law has mid-rise at the origin. It is because −. There are two types of uniform quantization. The base band signal which is band limited is obtained and this signal is used to … These are the error correcting bits. Functional Block Diagram of a Binary Digital Communication System A/D Converter Binary Sequence Analog Waveform Source encoder Channel encoder Modulator Physical Waveform Channel Channel Demodulator Decoder Source Decoder Binary Sequence D/A Converter Analog Waveform EE4367 Telecom. For a 1, the voltage level gets a transition from + to – or from – to +, having alternate 1s to be of equal polarity. Base-band signal also called low-pass signal. Figure 4.1-1 presents a block diagram for a two-node, one-way M-ary communications system. If there are ‘n’ number of connections, then the frame is divided into ‘n’ time slots. The regenerative pulse compared with the original and received pulse, will be as shown in the following figure. Here, the information is reproduced without any loss. [e_p(nT_s)]$, $\widehat{x}(nT_s)$ = the previous value of the delay circuit, = (The previous output of the delay unit) + (the present quantizer output), $u(nT_s) = S \displaystyle\sum\limits_{j=1}^n sig[e_p(jT_s)]$, Accumulated version of DM output = $\displaystyle\sum\limits_{j = 1}^n v(jT_s)$, $= \displaystyle\sum\limits_{j = 1}^{n - 1} v(jT_s)$. The difference in these conditions help us gain knowledge on the probabilities of the occurrence of events. Instead of a pulse train, PCM produces a series of numbers or digits, and hence this process is called as digital. While the transition is from Low to High for the input bit 0. However, Hamming code is a better procedure than the previously discussed ones in error detection and correction. These will be discussed in subsequent chapters. To have a clear understanding, let us take a look at their comparisons. A digital signal is generally represented by a binary sequence. If no transition occurs at the beginning of the bit interval, then the input bit is 1. The following figure explains the concept of NRZ coding. The ISI is unwanted and should be completely eliminated to get a clean output. At the modulator’s input, the message signal’s even bits (i.e., 2nd bit, 4th bit, 6th bit, etc.) $S_i(t) = \sqrt{\frac{2E_s}{T_s}} \cos \left ( \frac{\pi}{T_s}\left (n_c+i\right )t\right )$ $0 \leq t \leq T_s \quad and \quad i = 1,2,3... \: ..M$. This consists of an equalizer along with an amplifier, a timing circuit, and a decision making device. The pulse duration and symbol bit duration are equal in NRZ type, while the pulse duration is half of the symbol bit duration in RZ type. The sampling rate of a signal should be higher than the Nyquist rate, to achieve better sampling. A larger step-size is needed in the steep slope of modulating signal and a smaller stepsize is needed where the message has a small slope. Data Communication Model. The Mid-Rise type is so called because the origin lies in the middle of a raising part of the stair-case like graph. The main function of a transmitter is to process an electrical signal obtained from the input transducer. For a linear code C, if every code word i.e., C = (C1, C2, ...... Cn) from C has a cyclic right shift of components, it becomes a code word. The frequency of the output signal will be either high or low, depending upon the input data applied. From equations 5 & 6, we get a possible structure for the demodulator. The same predictor circuit is used in the decoder to reconstruct the original input. This drawback is cleared in convolution codes. This unit has dealt with the introduction, the digitization of signals, the advantages and the elements of digital communications. There are many different error correcting codes depending upon the mathematical principles applied to them. Of them all, the digital modulation technique used is Pulse Code Modulation (PCM). In the absence of ISI, the output will be −. In this type of coding, there always occurs a transition in the middle of the bit interval. Depending on Signal specification or technology, the communication system is classified as follows: (1) Analog . The ASK modulated input signal is given to the Square law detector. Digital signals can be saved and retrieved more conveniently than analog signals. Hence, it contains a non-zero value. Hence, this is the equational representation of Mutual Information. The high signal closes the switch, allowing a carrier wave. As mentioned before, the predictor assumes a value, based on the previous outputs. Hence, the timing circuit, allots the timing interval for sampling at high SNR, through the received pulses. The spacing between the two adjacent representation levels is called a quantum or step-size. Following is the diagram for the same. We have used two voltage levels to send a single bit over a single signal. Their working of each of the components is detailed as follows. This section increases the signal strength. Fig. Components and Basic Block Diagram of Data Communication. Hence, the interpretation of eye pattern is an important consideration. The following figure clearly depicts this. This is a form of distortion of a signal, in which one or more symbols interfere with subsequent signals, causing noise or delivering a poor output. Here we have one transmitter and multiple receivers, therefore it is known as broadcasting channel. Example − The sound signal received. This synchronous demodulator is a bit complex than asynchronous type demodulators. The probability of error is much reduced. In the coming chapters, we will learn about the concepts of Digital communications, in detail. The main advantage of spread spectrum communication technique is to prevent “interference” whether it is intentional or unintentional. Low pass filter is used for many reasons, but the prominent reason is noise elimination for out-of-band signals. Both the Narrow band and Spread spectrum signals can be understood easily by observing their frequency spectrum as shown in the following figures. BCH codes are named after the inventors Bose, Chaudari and Hocquenghem. As the sampling interval is reduced, the signal correlation will be higher. Here, the transmitted signal itself can be used as a reference signal. The occurrence of cross-talk is very rare in digital communication. If $\frac{H(\delta)}{T_s} = \frac{C}{T_c}$ then the system is said to be signaling at a critical rate. The low pass filter suppresses the higher frequencies and gives an envelope detected output from which the comparator delivers a digital output. In the process of encoding, the parity bits are subtracted from the whole data and the message bits are encoded. The data communication model is consists of three systems such as source, transmission and destination system. In this, $\frac{C}{T_c}$ is the critical rate of channel capacity. For example, a frequency was allotted to sender 1 for a particular period of time. There are two variations in Unipolar signaling −. A theorem called, Sampling Theorem, was stated on the theory of this Nyquist rate. Entropy can be defined as a measure of the average information content per source symbol. This technique is used to transmit a signal over a single communication channel, by allotting one slot for each message. Pulse Code Modulation (PCM) Vs Differential Pulse Code Modulation (DPCM), LATEST SCIENTIFIC RESEARCHES (Includes Videos), SECRETS OF THE UNIVERSE (With Awesome Videos), EVERYDAY SCIENCE EXPLAINED (With Interesting Videos), TECHNOLOGY AND TROUBLESHOOTING (Includes Video Tutorials), Engineering Topics (With Video Lectures in HD), MODULATION TECHNIQUES (Analog and Digital), PULSE MODULATION Techniques (PAM, PWM, PPM, PCM), COMMUNICATION SYSTEMS (ANALOG AND DIGITAL), RANDOM VARIABLES and PROBABILITY DISTRIBUTION, Free Google Games to Play Now- elgoog Games- (Atari Breakout, Google Snake Game, T Rex Dash, Pacman), Low Level and High Level Modulation Block Diagram (AM Transmitter Block Diagram), Conventional AM Vs DSB-SC Vs SSB-SC Vs VSB - Comparison of AM Techniques - Types of Amplitude Modulation, FREQUENCY SPECTRUM OF AMPLITUDE MODULATION (WAVEFORMS AND EQUATIONS DERIVATION), PULSE MODULATION TECHNIQUES (PAM, PWM, PPM, PCM), Thevenin Theorem - Thevenin Equivalent Circuit - Applications and Limitations of Thevenin Theorem, Digital Modulation Techniques (ASK, FSK, PSK, BPSK) - Amplitude, Frequency and Phase Shift Keying, Meridional and Skew Rays (Optical Fiber Communication), STEP INDEX OPTICAL FIBER (MULTIMODE AND SINGLE MODE STEP INDEX FIBERS), Slope Overload Distortion and Granular (Idle Noise), Quantization Noise in Delta Modulation. µ-law is used in North America and Japan. These combinations act as demodulators and the decision circuit chooses which output is more likely and selects it from any one of the detectors. This process of coding is chosen so as to avoid overlap and distortion of signal such as inter-symbol interference. The owner of this blog will not be liable for any inaccuracy or incompleteness of any information on this blog (Website) or found by following any link given on this blog (website). The most occurring loss, as we have discussed, is the ISI. View Answer: Answer: Thermal, Shot, Partition, 1/f, transit-time. The following figure gives a detailed idea on this classification. Cyclic codes are used for error correction. This is the output which is produced after the whole process. Following is the diagrammatic representation. The blue line represents analog signal while the brown one represents the quantized signal. The Equalizer circuit compensates these losses by shaping the received pulses. This whole process is repeated in a reverse pattern to obtain the original signal. From the models so far discussed, we have learnt the difference between NRZ and RZ. Delta Modulation gives a better output than PCM. This helps in restoring the signals from the losses occurred. The function which describes how the power of a signal got distributed at various frequencies, in the frequency domain is called as Power Spectral Density (PSD). The functional blocks at the transmitter are responsible for processing the input message, encoding, modulating, and transmitting over the communication channel. These three events occur at different times. I'm Lalit Vashishtha, A Passionate Blogger and YouTuber, Assistant Professor in an Engineering College. But why we need to convert non electrical signals into electrical signals? Functions of each block: Now, after a while, sender 1 hops to the other frequency and sender 2 uses the first frequency, which was previously used by sender 1. The output of a FSK modulated wave is high in frequency for a binary High input and is low in frequency for a binary Low input. It removes the redundant bits (unnecessary excess bits, i.e., zeroes). This correlation between the pulses may be understood as introducing ISI in the transmitted signal in an artificial manner. The various massage is the form of words, group of word, code, symbol, sound signal etc. It is denoted by $H(x \mid y)$, Let us consider a channel whose output is Y and input is X, Let the entropy for prior uncertainty be X = H(x), (This is assumed before the input is applied), To know about the uncertainty of the output, after the input is applied, let us consider Conditional Entropy, given that Y = yk, $$H\left ( x\mid y_k \right ) = \sum_{j = 0}^{j - 1}p\left ( x_j \mid y_k \right )\log_{2}\left [ \frac{1}{p(x_j \mid y_k)} \right ]$$. The loudspeaker works as the destination in the communication system. The analog multiplexing techniques involve signals which are analog in nature. This is a random variable for $H(X \mid y = y_0) \: ... \: ... \: ... \: ... \: ... \: H(X \mid y = y_k)$ with probabilities $p(y_0) \: ... \: ... \: ... \: ... \: p(y_{k-1)}$ respectively. The carrier generator, sends a continuous high-frequency carrier. BPSK is basically a Double Side Band Suppressed Carrier (DSBSC) modulation scheme, for message being the digital information. The transmitted M number of signals are equal in energy and duration. If there occurs a transition at the beginning of the bit interval, then the input bit is 0. The Digital Communication Notes Pdf (DC Notes) book starts with the topics covering Model of Digital Communication Systems, PCM Generation and Reconstruction, ASK Modulator. This is a transducer which takes a physical input and converts it to an electrical signal (Example: microphone). Encoding is the process of using various patterns of voltage or current levels to represent 1s and 0s of the digital signals on the transmission link. The causes of ISI should also be resolved in order to lessen its effect. This residual effect is called as Inter Symbol Interference. When the effect of ISI increases, traces from the upper portion to the lower portion of the eye opening increases and the eye gets completely closed, if ISI is very high. To avoid the abrupt phase discontinuities of the output waveform during the transmission of the message, a clock is applied to both the oscillators, internally. For a zero binary input, the phase will be 0° and for a high input, the phase reversal is of 180°. The spectral line present at the symbol rate can be used as a clock. Hence, this is also a good sampling rate. If there is no noise present, then the modulator output equals the demodulator input. The sampling theorem, which is also called as Nyquist theorem, delivers the theory of sufficient sample rate in terms of bandwidth for the class of functions that are bandlimited. Information source :-. Following is the basic block diagram of communication system. But the same ISI if used in a controlled manner, is possible to achieve a bit rate of 2W bits per second in a channel of bandwidth W Hertz. (2) Digital. Cyclic codes follow this cyclic property. Jitter is the short-term variation of the instant of digital signal, from its ideal position, which may lead to data errors. 1. Digital communication is one of the most commonly used mode of communication in the current scenario. Hence, the clock rate is double the data transfer rate and thus the modulation rate is also doubled. Some of these techniques, modulate one parameter of the carrier signal, such as amplitude, phase, and frequency. The end or start of a bit will not be indicated and it will maintain the same voltage state, if the value of the previous bit and the value of the present bit are same. The bandwidth efficiency of M-ary PSK decreases and the power efficiency increases with the increase in M. So far, we have discussed different modulation techniques. The following image is the diagrammatic representation of FSK modulated waveform along with its input. The elements which form a digital communication system is represented by the following block diagram for the ease of understanding. Block Diagram of Communication Systems; Objective Questions; Types Of Communication Systems. The predictor circuit in DPCM is replaced by a simple delay circuit in DM. Mutual information of a channel is related to the joint entropy of the channel input and the channel output. Hence, we get the equation for Power Spectral Density. A Stair-case approximated waveform will be the output of the delta modulator with the step-size as delta (Δ). The various massage is the form of words, group of word, code, symbol, sound signal etc. Get High Quality Content on Science, Technology and Engineering Topics along with VIDEO Content in HD. By recovering the band-limited message signal, with the help of the mixer circuit and the band pass filter, the first stage of demodulation gets completed. Such a signal is called as duo-binary signal. 9. The figure below shows the block diagram representing a PCM system. Hence, it contains a zero value. These digital modulation techniques are further discussed. To make the signal free from ISI, and to ensure a maximum signal to noise ratio, we need to implement a method called Equalization. Microwave and Digital communication Lab 4 PCM Operation (with DC input) Modulation: 8. If the letter E is considered, which is mostly used, it is denoted by “.” Whereas the letter Q which is rarely used, is denoted by “--.-”. Predictor input is the sum of quantizer output and predictor output, $$u(nT_s) = \widehat{x}(nT_s) + v(nT_s)$$, $u(nT_s) = \widehat{x}(nT_s) + e(nT_s) + q(nT_s)$. Denoting the Mutual Information as $I(x;y)$, we can write the whole thing in an equation, as follows. But, historically, these codes have been classified into Linear block codes and Convolution codes. We need a sampling frequency, a frequency at which there should be no loss of information, even after sampling. The block diagram of Synchronous FSK detector consists of two mixers with local oscillator circuits, two band pass filters and a decision circuit. This is due to the transmission characteristics of the channel. In a communication system, the transmitter is located at one place, the receiver is located at some other place (maybe far or near) separate from the transmitter and the channel is that physical medium that connects them. This step referred to as pulse modulation or base-band modulation. In the absence of noise, the encoded receiver input will be the same as the encoded transmitter output. To find the process of obtaining this ASK modulated wave, let us learn about the working of the ASK modulator. If the data is a High i.e., 1, then the phase of the signal is reversed, as with NRZI, invert on 1 (a form of differential encoding). The channel encoder, does the coding for error correction. A channel is the medium through which the message travels from the transmitter to the receiver. Draw the block diagram of an analog communication system and explain the main function ofeach block (unit) ofyour diagram. Set DC source to some value say 1 V with the help of multimeter and connect it to the A/D converter input and observe the output LED’s. For them to be represented mathematically, we have LPC and digital multiplexing techniques. Hence in this method, we have as many as 729 (3^6) combinations for signal and 256 (2^8) combinations for bits. These bits are mapped with the blocks which has n bits in each block. The ASK modulator block diagram comprises of the carrier signal generator, the binary sequence from the message signal and the band-limited filter. There are a few techniques which have paved the basic path to digital communication processes. Then, pulse waveforms are assigned that represented these symbols. To process this redundant information and to have a better output, it is a wise decision to take a predicted sampled value, assumed from its previous output and summarize them with the quantized values. (i) The necessary components of a communication system are an information source, input transducer, transmitter, communication channel, receiver, and destination. The reverse process, i.e., extracting the number of channels from one, which is done at the receiver is called as de-multiplexing. The above figure shows the basic block diagram of a typical data communication system. According to the Einstein-Wiener-Khintchine theorem, if the auto correlation function or power spectral density of a random process is known, the other can be found exactly. Hence, these techniques are bandwidth efficient. The Fourier Transform of the signal xs (t) is, $$X_s(w) = \frac{1}{T_{s}}\sum_{n = - \infty}^\infty X(w-nw_0)$$, Where $T_s$ = Sampling Period and $w_0 = \frac{2 \pi}{T_s}$, Let us see what happens if the sampling rate is equal to twice the highest frequency (2W). If the message is not altered, then it is called as systematic code. To discretize the signals, the gap between the samples should be fixed. The signal level is checked twice for every bit time, both initially and in the middle. Spread spectrum technique is used to avoid signal jamming. Let us consider a discrete memoryless channel (δ) with Entropy H (δ), Ts indicates the symbols that δ gives per second, Hence, the maximum capability of the channel is C/Tc. It is generally observed that, we seek the help of Fourier series and Fourier transforms in analyzing the signals and also in proving theorems. We will see the block diagram of communication system (electronic Communication system) with the explanation of each block. Solution: 3. Presence of low frequency components may cause the signal droop. Though the features are good, these signals are prone to interference. Spread of energy is low and concentrated. This signal to get converted into digital, has to undergo sampling and quantizing. This technique is suitable for transmission over AC coupled lines, as signal drooping doesn’t occur here. The Delta Modulator comprises of a 1-bit quantizer and a delay circuit along with two summer circuits. M is the number of conditions, levels, or combinations possible with N bits. This equation shows that the ith bit transmitted is correctly reproduced. (2) Digital In digital technology, the data are generated and processed in two states: High (represented as 1) and Low (represented as 0). The following figure shows the image of an eye-pattern. If digital signals are multiplexed, it is called as digital multiplexing. In Differential Phase Shift Keying (DPSK) the phase of the modulated signal is shifted relative to the previous signal element. Block diagram of a communication system The type of modulation, where the sampling rate is much higher and in which the stepsize after quantization is of a smaller value Δ, such a modulation is termed as delta modulation. In the next chapter, let us discuss about the concept of Quantization. Acceptance Angle and Numerical Aperture (NA) (Opti... Current Affairs 7 August 2018 in Hindi/ Daily Curr... Current Affairs 6 August 2018 in Hindi/ Daily Curr... Intelligence Agencies of the World/ Intelligence A... North american islands list Islands in north america. The block diagram shown depicts the general form of a communication system. Any linear block code can be a systematic code, until it is altered. Quantization is representing the sampled values of the amplitude by a finite set of levels, which means converting a continuous-amplitude sample into a discrete-time signal. An example of this type is Alternate Mark Inversion (AMI). Both the mid-rise and mid-tread type of uniform quantizers are symmetric about the origin. Then it is passed to a shaper circuit, which is a comparator or a Schmitt trigger circuit, to recover the original binary data as the output. All content provided on this blog is for informational purposes only. View Answer: Answer: Source, Transmitter, Channel, Receiver, Destination. The design of the modulator and the demodulator is simple. In the receiver, the Demodulation (detection) of the modulated signal takes place. The difference between an input value and its quantized value is called a Quantization Error. If the bit rate is a sub-multiple of the carrier frequency, then the bit clock regeneration is simplified. (i) shows the block diagram of a general communication system, in which the different functional elements are represented by blocks. In analog multiplexing, the most used technique is Frequency Division Multiplexing (FDM). Following is the representation of the structure of code word, according to their allocation. Figure 1.1-1 illustrates the functional diagram and the basic elements of a digital communication system. For reliable communication to be established, we need to have a quality output. Although spread spectrum techniques were originally designed for military uses, they are now being used widely for commercial purpose. The following figure shows how an analog signal gets quantized. Filters, two band pass filters ( BPFs ), tuned to space and Mark frequencies in! Introduces bit errors and burst errors should also be inserted at the places where the signal sample at instant. Frame is divided into FDM, WDM, and a decision circuit there is no mixing up and of. Broadcast and telephone transmission are common examples of analog signals using time Division multiplexing is first. Represented mathematically, we get the equation for power spectral Density communication over analog communication, known as channel! Over analog communication, known as broadcasting channel are responsible for the resultant quantized signal is... Filter is used to produced required message which has n bits if transmitted, k bits in block... 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