Question

Basic Properties of Convolutional Codes a convolutional encoder has finite memory, it can easily be represented bu m diagram. In the state-transition diagram, each state of the convolution 13.3.1 output(s) are specified. The number of lines emerging from each state is, therefoe pondi number of possible inputs to the encoder at that state, which is equal to 2. T ines merging at each state is equal to the number of states from which a tran tis represented by a box, and transitions between states are denoted by lines these boxes. On each line, both the input(s) causing that transition and the cortes equal t The number nsition that leave the to this state. This is equal to the number of possible combinations of bit the encoder as the k bits enter the encoder. This, again, is equal to 2. Figure 13.11 the state transition diagram for the convolutional code of Figure 13.10. more popular method, to describe convolutional codes is specify A second, and their trellis diagram. The trellis diagram is a way to show the transition between va states as the time evolves. The trellis diagram is obtained by specifying all states on xis along the time axis. Then, each transiti Ion vertical axis and repeating this vertical a a state to another state is denoted by a line connecting the two states on two d vertical axes. In a sense, the trellis diagram is nothing but a repetition of the state-transt diagram along the time axes. As was the case with the state-transition diagram, we have 2 branches of the trellis leaving each state and 2 branches merging at each state. the case where k I, it is common to denote the branch corresponding to a 0 in Figure 13.10 A rate convolutional encoder

Answer 1

yo