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Right answer is (b) False

The explanation: Rather than decoding each received SIGNAL by itself, MLSE tests all possible data sequences by USING a channel IMPULSE RESPONSE simulator within the algorithm. It chooses the data sequence with maximum PROBABILITY as the output.

Correct choice is (d) REED Solomon codes

The best explanation: RS codes achieve the largest possible minimum distance, dmin of any linear code. They are non-binary codes which are CAPABLE of correcting ERRORS that APPEARS in bursts.

Right option is (d) STATISTICAL distribution of transmitted power

The explanation is: The cost of the computing platform, the power budget and the radio propagation characteristics dominate the choice of an equalizer STRUCTURE and its ALGORITHM. Battery drain at the subscriber unit is ALSO a paramount consideration.

Right ANSWER is (b) Number of iterations

Explanation: Rate of convergence is required as number of iterations required for the algorithm to CONVERGE close ENOUGH to the OPTIMUM solution. It enables the algorithm to track statistical VARIATIONS when operating in non stationary environment.

The correct option is (a) Simple structure

The explanation is: The structure of LATTICE equalizer is more complicated than a linear transversal equalizer. But, NUMERICAL stability and FASTER convergence are TWO advantage of laatic equalizer. Also, its unique structure allows dynamic assignment of the most EFFECTIVE length of lattice equalizer.

The correct option is (d) Transmitter characteristics

The explanation is: The timespan over which an equalizer CONVERGES is a function of the equalizer ALGORITHM, the equalizer STRUCTURE and the time RATE of change of the multipath radio channel. Equalizers require proper retraining in order to maintain EFFECTIVE ISI cancellation.

The correct choice is (a) CONSTRAINT length

Best EXPLANATION: Constraint length determines the number of input data BITS that the current output is dependent UPON. The constraint length determines how powerful and complex the code is.

The correct answer is (d) Non linearity

The best I can explain: Block CODES are linear, systematic and cyclic in nature. Encoding and decoding techniques make USE of mathematical constructs KNOWN as FINITE fields.

The correct answer is (B) END

The explanation is: A systematic code is one in which the parity bits are appended to the end of the information bits. For an (n,k) code, the FIRST k bits are identical to the information bits, and the REMAINING (n-k) bits of each code word are linear COMBINATIONS of k information bits.

Right answer is (b) Time diversity

The best I can explain: SPACE diversity RECEPTION METHODS can be classified into four categories. They are selection diversity, feedback diversity, maximal ratio COMBINING and equal gain diversity.

Right answer is (C) Mean square error

The best I can EXPLAIN: LMS equalizer is a robust equalizer. It is used to minimize mean square error (MSE) between the desired equalizer output and the actual equalizer output.

The CORRECT answer is (a) True

Explanation: The choice of ALGORITHM and its corresponding rate of convergence depends on the channel data rate and coherence time. The speed of the mobile unit DETERMINES the channel FADING rate and the Doppler spread, which is directly related to coherence time of the channel.

Correct answer is (b) False

Explanation: LTE is well behaved when the channel SPECTRUM is comparatively FLAT. But if the channel is severely DISTORTED or exhibits null in the spectrum, the performance of LTE deteriorates and MSE of DFE is better than LTE.

Right OPTION is (B) False

The explanation is: Non-LINEAR EQUALIZERS are used in applications where the channel distortion is too severe for a linear equalizer to handle. They are most COMMONLY used in practical wireless communication.

Correct CHOICE is (a) Trained

Explanation: When an EQUALIZER has been properly trained, it is said to have converged. Equalizers are commonly used in digital communication systems where user DATA is segmented into SHORT time blocks or time slots.

The correct option is (C) Inverse filter

Easy explanation: An equalizer is ACTUALLY an inverse filter of the channel. The goal of EQUALIZATION is to satisfy that the combination of the transmitter, channel and receiver be an all pass channel.

The correct ANSWER is (a) MAXIMUM likelihood

The best explanation: VITERBI ALGORITHM performs maximum likelihood decoding of convolutional codes. The algorithm was first DEVELOPED by A.J. Viterbi. It is one of the most important algorithm used for decoding convolutional codes.

The CORRECT answer is (d) REED Solomon codes

The best I can explain: The most important and most COMMON CLASS of non binary is the family of codes known as Reed Solomon codes. BCH codes are among the most popular BLOCK codes that exist for a wide range of rates, achieve significant coding gains.

Right answer is (c) Macroscopic DIVERSITY technique

For EXPLANATION: Large scale fading is mitigated with macroscopic diversity techniques. It is done by selecting a base station which is not shadowed when others are, the mobile can IMPROVE substantially the AVERAGE signal to noise ratio.

Right answer is (C) Reflection coefficient

Easiest EXPLANATION: Decorrelation of the signal in each polarization is caused by multiple reflections in the channel between MOBILE and base station antenna. Reflection coefficient for each polarization is different, which RESULTS in different amplitudes and phases for each reflection.

Right choice is (C) Passive codes

For EXPLANATION: There are three BASIC types of error correction and DETECTION codes. They are block codes, convolutional codes and turbo codes. A channel coder operates on digital message data by encoding the source information into a code sequence.

Correct choice is (d) OPERATES on continuous TIME signal

For explanation: Matched filter operates on the continuous time signal, whereas maximum likelihood sequence estimation (MLSE) equalizer and channel ESTIMATOR rely on discretized samples. MLSE is optimal in the sense that it minimizes the probability of sequence error.

Right answer is (a) Non-zero ELEMENTS in the codeword

Easy EXPLANATION: The weight of a CODE is GIVEN by number of non-zero elements in the codeword. For a binary code, the weight is BASICALLY the number of ones in the codeword.

The correct option is (b) False

For explanation: Frequency diversity is not good for LOW traffic conditions. This TECHNIQUE has a disadvantage that it not only requires spare bandwidth but ALSO requires that there be as many RECEIVERS as there are channels used for frequency diversity. HOWEVER, for critical traffic, the expense may be justified.