ICIECA 2014 Paper

1. REALIZATION OF COST-EFFECTIVE
MULTIPLIER FOR HIGH SPEED DIGITAL
SIGNAL PROCESSING ARCHITECTURES
PRESENTED BY:
Veera Boopathy.E (M.E-VLSI DESIGN, VSBEC, Karur)
Bharath Kumar.M (Asst.Professor-ECE, VSBEC, Karur)
Saravanan.S (Asst.Professor-ECE, VSBEC, Karur)

2. ABSTRACT
 Low-cost FIR designs using rounded truncated multipliers.
 Bit width optimization and hardware resources are equally
considered without sacrificing frequency response and
output signal precision.
 To minimize total area cost non-uniform coefficient
quantization with proper filter order is proposed.
 MCM in direct FIR structure is implemented using
improved truncated multipliers.
 Proposed designs achieve best area and power compared
with previous FIR design approaches.

3. INTRODUCTION
 FIR digital filter is vital component in DSP and
communication systems.
 Applied in portable applications with reduced area and
power.
 FIR filter of order M is
 Two FIR structures are direct form and transposed form
for a FIR filter.

4. PURPOSE OF WORK
 In many multimedia and DSP applications multiplication
operations have fixed-width property.
 Thus required to truncate product bits to necessary
precision to reduce area cost, leading to design of truncated
multipliers.
 A truncation algorithm is proposed for efficient hardware
reduction.
 The proposed algorithm considers following to minimize
the overall error in the final result
 elimination of unwanted LSBs of partial product
 addition of correction bit at appropriate bit position

5. DIRECT FORM
STRUCTURE
TRANSPOSED FORM
STRUCTURE
Parallel multiplication of
delayed signals with
respective filter coefficients
then accumulation of entire
product terms.
Current input signal and
coefficients are multiplied
then individually
go through SA and delay
elements.

6. CLASSIFICATION OF FIR FILTER
HARDWARE IMPLEMENTATION
DIGITAL FIR FILTER
HARDWARE
IMPLEMENTATION
MULTIPLIER
LESS BASED
MEMORY BASED
LOOK-UP-TABLE
(LUT)
DISTRIBUTED
ARITHMETIC
(DA)

7. MULTIPLIER-LESS
BASED
MEMORY BASED
LUT BASED DA BASED
 Realize MCM
with shift and add
operations and then
use CSD and CSE
to minimize adder
cost of MCM
 LUT-based
design stores odd
multiples of input
signal in ROMs to
realize constant
multiplications in
MCM.
DA-based design
recursively
accumulate bit-
level partial results
for inner product
computation.

8. STAGES IN DIGITAL FIR FILTER DESIGN
AND IMPLEMENTATION
FREQUENCY RESPONSE SPECIFICATION
FINDING FILTER ORDER AND
COEFFICIENTS
COEFFICIENT QUANTIZATION
HARDWARE OPTIMIZATION

9. PROPOSED DESIGN
• Low-cost FIR filters based on direct structure with
faithfully rounded truncated multipliers is
proposed.
• MCMA module is realized by accumulating all
PPs where unnecessary PPBs are removed without
affecting final precision of output.
• Bit widths of all filter coefficients are minimized
using non-uniform quantization to reduce
hardware cost still satisfying specification of
frequency response.

10. TRUNCATED MULTIPLIER DESIGNS
EARLIER VERSION
TRUNCATED MULTIPLIER DESIGNS
IMPROVED VERSION

11. MCMAT PROCEDURE IN EARLIER
VERSION
MCMAT PROCEDURE IN IMPROVED
VERSION

12. EARLIER TRUNCATED MULTIPLIER ALGORITHMIC PROCEDURE

13. PROPOSED TRUNCATED MULTIPLIER ALGORITHMIC PROCEDURE

14. MULTIPLICATION / ACCUMULATION
USING INDIVIDUAL PP COMPRESSION
MULTIPLICATION / ACCUMULATION
USING COMBINED PP COMPRESSION

15. OVERALL FIR FILTER ARCHITECTURE USING MCMAT

16. RESULTS AND COMPARISONS

17. CONCLUSION
 MCMAT direct FIR structure leads to minimum area, cost
and power utilization even if several earlier designs are
build on transposed form.
 Reduced area, power and cost FIR filter designs is
achieved with respect to coefficient bit width optimization
and hardware sources realization.