Communications electronics by frenzel pdf

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Principles of electronic communication systems / Louis E. Frenzel Jr. —Fourth edition. pages cm. Includes index. ISBN (alk. paper) — ISBN . COMMUNICATIONS ELECTRONICS by Frenzel CHAPTER 1: Introduction to Electronic Communications CHAPTER 2: Amplitude Modulation and. Principles of Electronic Communication Systems 4th Ed __ Louis E ELECTRONIC COMMUNICATION SYSTEM BY GEORGE

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Communications Electronics By Frenzel Pdf

Advanced Electronic Communications Systems Wayne Tomasi Sixth Edition Advanced Electronic Communication system/George Kennedy, Bernard Davis. Communication Electronics book. Read 11 reviews from the world's largest community for readers. This text introduces basic communication concepts and cir. This is the Chapter list of the book "COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. Each chapters consists of summary notes of the important terms.

If the signal level is usually high, the RF amplifier may not be needed. Diode, double balanced, singly balanced. Double-tuned coupled circuits, crystal, ceramic, or SAW filters. AWGN is a standard random noise created for the purpose of testing receivers and comparing selectivity. Limiting is allowed in FM receivers that have a demodulator that must have a fixed amplitude input signal for proper operation. Collector current. Automatic gain control AGC. In reverse AGC, increasing the collector current increases the gain. By changing the emitter current. Squelch; muting. The local oscillator frequency is equal to the received signal frequency. CTCSS is a squelch system that is activated only by the receipt of a unique tone signal which provides channel privacy and security.

Attenuation refers to a loss introduced by a circuit or component. When gain is converted to decibels, the overall gain of an electronic circuit can be computed by adding the individual gains expressed in decibels. When a decibel value is computed by comparing a power value to 1 mW, the result is a value called the dBm.

Circuits made up of inductors and capacitors that resonate at specific frequencies are called tuned circuits. The reactance of a capacitor is inversely proportional to the value of capacitance and operating frequency. A n inductor also called a coil or choke is simply a winding of multiple turns of wire.

An important characteristic of an inductor is the ratio of inductive power to resistive power referred to as its quality factor. When the inductive and capacitive reactances are equal, resonance occurs. The bandwidth of a tuned circuit is defined as the difference between its upper and lower cutoff frequencies.

Remember Blooms: 2. Subtract The PC video monitor display of an SDR consists of a frequency spectrum plot, a waterfall display, and numerical frequency display plus any controls volume, etc. The IF is usually the difference between the local oscillator frequency and the received signal. In this case, it is zero. However, the signal has sidebands at This is called a direct conversion receiver.

The IF is the original modulating signal. If the signal is voice, the IF amplifier is a selective audio amplifier. Answers to Problems 1. Microwave frequencies. Chapter 10 Answers to Questions 1.

No; it is the process of transmitting multiple signals over a single channel. Signals to be multiplexed are used to modulate subcarriers of different frequency.

All are mixed together and transmitted in a common channel bandwidth. Linear mixer or analog summer. Linear mixer.

Book Communication Electronics 3rd Ed- Frenzel 2001

Missile and aircraft testing, space exploration, industrial monitoring and control. Spatial multiplexing allows multiple signals to use the same frequency but prevents interference between them by using low power and directional antennas.

AM, DSB. A bandpass filter centered on the subcarrier frequency. The signals are sampled sequentially, and the samples transmitted by interleaving them over time. Pulse-amplitude modulation PAM. Clock recovery circuits. Synchronizing signals and clock recovery circuits ensure that the receiver stays in step with the transmitted signals. Low-pass filter. A binary code representing the desired channel is contained in a counter or register which is decoded.

A PAM signal is transmitted by having the pulses amplitude modulate a carrier which is then amplified by a linear power amplifier. Phase-locked loop. Better noise immunity and more easily reconstructed binary signals distorted by the transmission process.

Baseband techniques are used to transmit T-1 signals; that is, the digital data is placed on the medium twistedpair cable, coax, fiber-optic cable, or audio link , as opposed to the signal being used to modulate a carrier.

Half-duplexing means two way transmission where one party transmits and the other listens. Full-duplex means that both parties may transmit and receive at the same time.

Frequency division duplexing divides a segment of spectrum into channels some of which are assigned for transmission at one end and reception at the other end and vise versa.

Time division duplexing defines different time slots in transmissions that are for transmission or reception. B TDD is more complex because of the timing and synchronization requirements of the method. Bit rate 1. Bit rate Answers to Critical Thinking 1. Separate binary data sources may modulate subcarriers on different frequencies. The subcarriers are summed, and the resulting composite transmitted as an FDM signal. Chapter 11 Answers to Questions 1. The telegraph.

Communication Electronics by Frenzel 3rd Edition Pdf

Morse code. You cannot distinguish between uppercase and lowercase letters with Morse code. Baudot code. To ring a bell, transmit the BEL code Serial and parallel.

Reviewer in Communications Electronics by Louis Frenzel

Start and stop bits. Baud rate. A symbol is any change in the transmitted signal during a bit interval such as amplitude, frequency, or phase.

Each symbol can represent two or more bit combinations. Synchronous transmission is faster because start and stop bits are not used on each transmitted byte; the total number of bits to be transmitted in a given time is thus less.

The message words are sent serially in a fixed format of a specific number of words in a block. A preamble precedes the block, and a postamble error code ends the transmission. Space 0 and mark 1. Two or more successive binary 0 or 1s. Bipolar RZ and Manchester. No average DC buildup on the transmission line. Manchester, biphase. High speeds are obtained by using a small modulation index and prefiltering the binary signal. Number of coding levels and the transmission speed baud.

Higher bps data rate. UART, scrambler, modulator, equalizer, line interface, adaptive receive equalizer, demodulator, descrambler, microcontroller. Modems are needed to convert digital signals to analog signals and vice versa to make them compatible with the standard voice-grade telephone system.

Modems are used with any computer that must communicate with another computer over long distances using the telephone system. A scrambler ensures that long strings of binary 0s or 1s are broken up into replacement codes with few successive 0 or 1 bits. Balanced modulator. A carrier recovery circuit, usually a phase-locked loop.

Differential BPSK. XNOR gate and a 1-bit delay flip-flop. Shift register. AM and PSK. Trellis code modulation is a form of QAM, used at data rates of bps or above, that incorporates a coding scheme that makes error detection and correction faster and easier.

It is used because at faster data rates over the telephone system the bit error rate is much higher than at rates less than bps. The process of modifying an intelligence signal in such a way that its spectrum is spread over a wide frequency range rather than being confined to a narrow singlechannel bandwidth.

Frequency-hopping and direct-sequence SS.

A frequency synthesizer. A pseudorandom sequence generator.


Random background noise. The identifying characteristic of a spread spectrum signal is the unique pseudorandom code being used. Dwell time. A shift register with XOR feedback or a specially programmed microcomputer. The PSN signal is a unique binary code sequence used for each station operating over a shared spectrum. It allows one station to be distinguished from another. Synchronizing the receiver to the desired signal. Data security and resistance to jamming or interference from other signals.

Cellular telephone, satellite, and radar. Voice signals are converted to serial digital data before they are sent to the SS equipment. Code division multiple access CDMA. Redundancy, special codes, encoding methods, parity, block-check character, cyclical redundancy check. Repeat the transmission until it is correctly received.

Reed Solomon. Bit error rate BER. Parity bit. Block-check code, or BCC. The corresponding bits in each word are added without carry to form the blockcheck character.

Vertical redundancy check. XOR gate.

Longitudinal redundancy check. A block of data is treated as if it were one very large binary number. It is divided by a smaller binary number called the generating function. The resulting quotient is abandoned, and the remainder is retained. The remainder is the CRC. A shift register with feedback through XOR gates. A CRC is generated at the receiver using the received data block.

It is then compared to the received CRC. If the two match, the data is correct. The sum is zero , indicating no errors in a bit position. Trellis, Viterbi, turbo recursive codes. The last field in a protocol frame is usually a block check sequence or CRC for error detection. A CRC word. Interoperability refers to the ability of one type of equipment to operate compatibly and communicate with the equipment of another manufacturer. Use protocols based on the OSI layers. Applications, presentation, session, transport, network, data link, physical.

Physical, data link, network, and applications. A temperature sensor such as a thermistor or resistive temperature device RTD monitors the temperature. This signal is serialized and packaged into a protocol packet by a microprocessor. It is then sent to modulate a low-power radio transmitter with antenna. The receiving antenna picks up the signal and recovers the original digital signal, which is then put back into parallel form and sent to an interface on the computer.

A program in the computer reads the data from the interface and stores it in memory. The program takes the data word and processes it so that it is displayed as the correct temperature on the video screen of the computer. Cellular telephone. Many phones could share a common band simultaneously. The conversations would be secure and private. Remote controls for TV sets, garage doors, and car doors, radio-controlled airplanes or cars—all via AC power lines.

Spread spectrum and OFDM are spectrally efficient because the disperse the very high data rate signals over a broad spectrum that is typically less spectrum than other methods use for the same data rate. B Chapter 12 Answers to Questions 1.

To permit individual PCs to communicate, share peripherals, and exchange software. The MAN is smaller. A cable TV network or a large company. About users per LAN. Star, ring, bus.

Ring and bus. The telephone system is a WAN. The fiber optic backbones of the Internet are WANs. Fiber optic cable. A SAN is a storage area network, a system made up of a redundant array of independent disks RAID or just a bunch of disks JBOD forming a storage facility for company or organization that can be accessed by servers and users via a high speed network. Wireless is the normal medium used in a PAN.

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