ECE122-FINALS-REVIEWER.docx

Extended binary coded decimal interchange-code, an eight bit fixed length character developed in 1962 by International Business Machines Corporation.

Sometimes called the Telex Code, was the first fixed length character developed for machines rather than for people.

A French postal engineer who developed the baudot code in 1875 and named after Emile Baudot, an early pioneer in telegraph printing.

Stands for United States of America Standard Code for Information Exchange, better known as ASCII-63.

The standard character set for source coding the alphanumeric character set that humans understand but computers do not (computers only understand 1s and 0s). It is a seven bit fixed-length character set.

It does not include spaces between characters. An example is Universal Product Code.

Caused by electrical interference from natural sources Classification of Data Com Errors: o single bit o multiple bit o burst Categories of Error Control: o Error Detection o Error Correction

A form of error detection by duplicating each data unit for the purpose of detecting errors.

An error detection bit.

The process of monitoring data transmission and deter mining when errors have occurred. It neither corrects errors nor identifies which bits are in error-they only indicate when an error has occurred.

The actual historical record of a system’s error performance.

The simplest error-detection scheme and is generally referred to as character parity.

The parity bit which is always a 1.

The parity bit which is not sent or checked

Form of redundancy error checking where each character has a numerical value assigned to it.

An error-correcting code used for correcting transmission errors in synchronous data streams. It requires the addition of overhead to the message, consequently increasing the length of a transmission.

Its literal meaning is “without synchronism”. In Data Com, it means “without a specific time reference”

Errors with two or more non-consecutive bits within a message.

When a receive station requests the transmit station to resend a message when the message is received in error.

A mathematician, who was an early pioneer in the development of errordetection and correction procedures, developed the Hamming Code while working at Bell Telephone Laboratories.

The difference in time between the beginning of a start bit and when it is detected.

Errors when two or more consecutive bits within a given data string are in error. It can affect one or more characters within a message.

Determine the LRCs for the following ASCII encoded message: THE CAT. Use even parity for LRCs.

For a 12 bit data string of 101100010010, determine the Hamming bits required.

This type of encoding uses three levels to represent a symbol

Which of the following has a serious problem on the presence of dc components?

In this encoding, a symbol is represented by 1.58 bits

Which of the following codes is an example of differential encoding?

The scrambling techniques, HDB3 and B8ZS, were based on the rules of

The oldest method of error detection

Five channels, each with a 100-kHz bandwidth, are to be multiplexed together. What is the minimum bandwidth of the link if there is a need for a guard band of 10kHz between the channels to prevent interference?

A supergroup has a bandwidth of

How many supergroups are multiplexed to create a master group?

On the multiplexing side, as the switch opens in front of a connection, that connection has the opportunity to send a unit onto the path. This process is called __.

A T-1 line is used to implement a DS-1 service with a data rate of

How many voice channels are supported in an E-1 line?

Which of the following uses modulo-11 in implementation?

Statistical TDM is also known as

Two channels, one with a bit rate of 100 kbps and another with a bit rate of 200 kbps, are to be multiplexed. What is the bit rate of the link?

The word bit was first used on an article published by

Bandwidth efficiency for 16 QAM with a rate of 10 Mbps

Determine the minimum bandwidth required to achieve a Eb / No of 14 dB for an 8-PSK system operating at 20 Mbps with a C/N of 11 dB.

Determine the minimum bandwidth for a 16-QAM modulator with an input bit rate of 20 Mbps

Minimum bandwidth for an BPSK modulated signal with a baud rate of 5000 is _______ Hz.

A binary source sends a 1 with a probability of 30%. Determine the entropy of this source

Calculate the minimum number of bits of information which must be given to permit the correct selection of one event out of 32 equiprobable events.

Maximum rate at which information can be transmitted through a channel

Information capacity is proportional to _____.

Channel capacity of a 6-MHz channel with a S/N ratio of 25 dB

A broadcast television channel has a bandwidth of 6 MHz. Calculate the maximum data rate that could be carried in a TV channel using a 16-level code. Ignore noise.

Minimum allowable bandwidth for a binary signal with a bit rate of 200 Kbps

Standard audio sampling rate in CD

The generating polynomial x7 + x5 + x4 + x2 + x + 1 is equivalent to

Which of the following is an application of FDM?