NANOSCALE STANDARD DIGITAL MODULES - Bio-Inspired and Nanoscale Integrated Computing - page 253

TABLE 9 . 8 . Frequency Assignments in the Second Multiplexer
Implementation
Node Sending frequency Receiving frequency

Binary select inputs f adc -

Analog select input Variable (f i ) f adc

Data inputs f out f i

Output - f out

9.3.5. Nanoscale Spin-Wave Demultiplexer
A demultiplexer is a device that takes a single input which selects one of many
data-output-lines and connects the single input to the selected output line.
A demultiplexer is often used in the receiver with a complimentary multiplexer
on the sender end. A 2 k -output demultiplexer is a combinational system that has
one binary input, k binary control (select), and 2 k data output. This module routes
the input data to the output selected by the control input; all other outputs are
zero [1]. The structure of a spin-wave demultiplexer consists of k select-input, one
data input, and N=2 k output nodes that are connected to a spin-wave bus, as
shown in Figure 9.8.
The implementation of the spin-wave demultiplexer is quite similar to the
spin-wave multiplexer (second method) implementation in which a distinct
frequency is assigned to each of the output nodes. In the first step the binary
select-input value is converted to analog value using a digital to analog converter.
Note that unlike the decoder and multiplexer, the implementation of the
demultiplexer requires no additional node to keep the analog select value, since
this value is received by the data-input node. The data-input node, which has
received the index of the output node, sends a signal with an amplitude equal to its
data on the specific frequency assigned to the output node. The output nodes are
tuned on distinct frequencies, therefore only the selected output node receives the

Data
input

N=2 K

Select inputs Outputs

s k − 1
2 K − 1

s k − 2 y N − 1

s 0 y 0 y 1 y 2

x

y 0

... ...

1

2 K − 2

f i

f adc

x

y i

x-value

Digital to analog
converter

y N − 1 Demultiplexer

...

S k − 1 S 0

Figure 9.8. Structure of a nanoscale spin-wave demultiplexer.