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ers (32%), but the design can run in real-time. It also
implies that only 3 channels can be implemented in
parallel for this FPGA chip.
Table 2: Synthesis report of the first channel of the auditory
subsystem.
Target Device XC2VP30
Synthesis Tool XST v10.1.01
Used Slices 993 7%
Used Slice Flip Flops 827 3%
Used 4 input LUTs 2,574 9%
Used RAMB16s 2 1%
Used MULT18X18s 44 32%
Max Frequency 17.505 MHz
5 CONCLUSIONS AND FUTURE
WORK
The paper presents the design and FPGA implemen-
tation of a bio-inspired hardware module that can be
used as a front end apparatus in a variety of embedded
auditory signal processing applications. The imple-
mentation consists of two sub-modules, Patterson’s
GFB and Meddis’ IHC, linked together to mimic the
behaviour of a single frequency channel of the audi-
tory periphery. The proposed design is fully param-
eterised and highly scalable. The design prototype
has been captured and then simulated using two inte-
grated tools, System Generator
TM
and AccelDSP
TM
both from Xilinx
TM
. The prototype works as ex-
pected and the design process is much faster than
the traditional hardware description language (HDL)
design flow. The resulting hardware structure was
too large to accommodate a 20-channel parallel au-
ditory subsystem; therefore, a time-shared multiplex-
ing scheme is envisaged for future implementations.
More optimisation can be achieved for the filter mod-
ules to improve the system performance and reduce
the number of multipliers. The ultimate goal is to
build a complete bio-inspired system that models the
signal processing of the whole human auditory sys-
tem.
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