# Communications [GATE (Graduate Aptitude Test in Engineering) Electronics]: Questions 54 - 59 of 106

Access detailed explanations (illustrated with images and videos) to **1176** questions. Access all new questions- tracking exam pattern and syllabus. View the complete topic-wise distribution of questions. *Unlimited Access, Unlimited Time, on Unlimited Devices*!

View Sample Explanation or View Features.

Rs. 450.00 -OR-

How to register? Already Subscribed?

### Passage

Consider a baseband binary PAM receiver shown below. The additive channel noise is with power spectral density . The low-pass filter is ideal with unity gain and cut-off frequency . Let represent the random variable .

, if transmitted bit

, if transmitted bit

Where, represents the noise sample value. The noise sample has a probability density function,

(This has mean zero and variance ) .

Assume transmitted bits to be equiprobable and threshold is set to .

## Question 54 (1 of 2 Based on Passage)

Appeared in Year: *2010*

### Question

MCQ▾The probability of bit error is

### Choices

Choice (4) | Response | |
---|---|---|

a. | ||

b. | ||

c. | ||

d. |

## Question 55 (2 of 2 Based on Passage)

Appeared in Year: *2010*

### Question

MCQ▾The value of the parameter α (in ) is

### Choices

Choice (4) | Response | |
---|---|---|

a. | ||

b. | ||

c. | ||

d. |

## Question 56

Appeared in Year: *2010*

### Question

MCQ▾The Nyquist sampling rate for the signal s (t) = is given by

### Choices

Choice (4) | Response | |
---|---|---|

a. | ||

b. | ||

c. | ||

d. |

## Question 57

Appeared in Year: *2010*

### Question

MCQ▾Consider an angle modulated signal . The average power of is

### Choices

Choice (4) | Response | |
---|---|---|

a. | ||

b. | ||

c. | ||

d. |

## Question 58

Appeared in Year: *2019*

### Question

MCQ▾A linear Hamming code is used to map 4-bit messages to 7-bit code words. The encoder mapping is linear. If the message 0001 is mapped to the code word , and the message is mapped to the code word , then the message is mapped to

(Carry One Mark Each)

### Choices

Choice (4) | Response | |
---|---|---|

a. | ||

b. | ||

c. | ||

d. | 1111111 |

## Question 59

Appeared in Year: *2019*

### Question

MCQ▾A single bit, equally likely to be 0 and 1, is to be sent across an additive white Gaussian noise (AWGN) channel with power spectral density . Binary signaling, with and , is used for the transmission, along with an optimal receiver that minimizes the bit-error probability. Let and form and orthonormal signal set. If we choose ) , we would obtain a certain bit-error probability Pb. If we keep , but take , for what value of E would we obtain the same bit-error probability Pb? (Carry One Mark Each)

### Choices

Choice (4) | Response | |
---|---|---|

a. | 1 | |

b. | 2 | |

c. | 3 | |

d. | 0 |