This set of Digital Communications Multiple Choice Questions & Answers (MCQs) focuses on “Abstraction and layering”. 1. Top layer is a) Physical media b) Application c) Design d) None of the mentioned 2. Entities also does a) Error correction b) A/D c) D/A d) All of the mentioned 3. In channel, delay is a) Fixed … Read more
This set of Digital Communications Multiple Choice Questions & Answers (MCQs) focuses on “Effects of fading and decision theory”. 1. Fading channel has memory. a) True b) False 2. How can frequency selective distortion be minimized? a) By using pilot signal b) By adaptive equalization c) By spread spectrum d) All of the mentioned 3. … Read more
This set of Digital Communications Multiple Choice Questions & Answers (MCQs) focuses on “Diversity technique and rake receivers”. 1. The technique for combining diversity signals are a) Feedback b) Maximal ratio c) Equal gain d) All of the mentioned 2. Diversity technique is used for combating a) Fading b) Error bursts c) Co-channel interference d) … Read more
This set of Digital Communications Multiple Choice Questions & Answers (MCQs) focuses on “Signal time spreading”. 1. Multiple isolated peaks in multipath components is called as a) Fingers b) Returns c) Fingers & Returns d) None of the mentioned 2. If delay time is greater than symbol time, _______ fading occurs. a) Frequency selective b) … Read more
This set of Digital Communications Multiple Choice Questions & Answers (MCQs) focuses on “Mobile radio propagation”. 1. What is the source for performance degradation? a) Thermal noise b) Man made noise c) Natural noise d) All of the mentioned 2. The received power is attenuated by a factor called a) Path loss b) Free space … Read more
This set of Digital Communications Multiple Choice Questions & Answers (MCQs) focuses on “Pretty good privacy”. 1. Pretty good privacy (PGP) security system uses a) Public key cryptosystem b) Private key cryptosystem c) Public & Private key cryptosystem d) None of the mentioned 2. Public key cryptosystem is used for the encryption of a) Messages … Read more
This set of Basic Digital Communication Questions & Answers focuses on “Public Key Crptosystems – 2”. 1. Cipher system can be solved effectively by statistically using a) Time of occurrence b) Frequency of occurrence c) Length of the message d) None of the mentioned 2. Encryption transformations are known as a) Diffusion b) Confusion c) … Read more
This set of Digital Communications Multiple Choice Questions & Answers (MCQs) focuses on “Public key cryptosystem – 1”. 1. In public key cryptosystem _____ keys are used for encryption and decryption. a) Same b) Different c) Encryption Keys d) None of the mentioned 2. In public key cryptosystem which is kept as public? a) Encryption … Read more
This set of Digital Communication Problems focuses on “Spread Spectrum “. 1. Spread spectrum is a ______ technique. a) Encoding b) Decoding c) Encoding & Decoding d) None of the mentioned 2. Spread spectrum can be used to transmit a) Analog data b) Digital data c) Analog & Digital data d) None of the mentioned … Read more
This set of Digital Communication aptitude tests focuses on “Stream Encryption and Commercial Applications”. 1. Which are called as substitution encryption techniques? a) Caesar cipher b) Trithemius cipher c) Caesar & Trithemius cipher d) None of the mentioned 2. In substitution technique encryption protection is more. a) True b) False 3. The standard building block … Read more
