Dr. Ramesh Rajagopalan Profile

Dr. Ramesh Rajagopalan

Sr Fellow Discipline Lead

SPIE Involvement:

Author

Publications (2)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 24 December 2003 Paper

Generalized causal moving average (GCMA) smoothing filter for real-time applications

Ramesh Rajagopalan

Proceedings Volume 5205, (2003) https://doi.org/10.1117/12.509703

KEYWORDS: Filtering (signal processing), Electronic filtering, Signal processing, Smoothing, Interference (communication), Control systems, Digital signal processing, Electromagnetic coupling, Data processing, Nonlinear filtering

Read Abstract +

Moving average filters are commonly used in industries for real-time processing of noisy data. Though they perform well in filtering out the noise, they introduce significant lag in the signal. The resulting peak value of the filtered signal at the operating point is likely to be lower due to averaging of higher and lower peak signals in the averaging interval. The generalized moving average smoothing filter by Golay-Savitzky preserves the higher moments and does not suffer from the limitations imposed by the conventional moving average filter. The smoothing strategy is derived from least squares fitting of a lower order polynomial to a number of consecutive points. Due to polynomial curve fitting as opposed to a line fitting in the case of conventional moving average filter, this filter preserves the higher frequency components of the signal and their line width. This paper presents a generalized casual moving average filter deduced using the concepts in Golay-Savitzky smoothing filter for real-time applications. Golay-Savitzky filter is non-casual, relies on the future data that is not available, hence not suitable for real-time applications. Further, the designed casual filter makes use of the filtered data as opposed to the original data in the case of Golay-Savitzky. This approach allows us to conduct frequency response studies to evaluate the quality and the applicability of the filter for various signals in the aircraft engines and other engineering applications. Frequency response studies cannot carried out using the Golay-Savitzky filter. This paper also investigates the performance of various polynomial orders in reproducing the signal from a noisy data. Some of the performance measures used are bandwidth, overshoots, and lags introduced by the filter. The mathematical technique to extract the signal and deduce the coefficients in off-line is also presented.

Proceedings Article | 23 January 1997 Paper

Parallel digital signal processing (DSP) vehicle controller for automated vehicles

Fabio Perelli, Ramesh Rajagopalan

Proceedings Volume 2903, (1997) https://doi.org/10.1117/12.265342

KEYWORDS: Digital signal processing, Image processing, Computing systems, Data processing, Roads, Motion controllers, Parallel processing, Parallel computing, Cameras, Sensors

Read Abstract +

This paper presents the design and implementation of a high performance vehicle controller based on parallel digital processing systems for automated vehicles. From the literature it has been observed that one of the main limiting factors of most automated vehicles rests on the available computing power. Most systems employ camera vision for guidance purposes. In some cases other sensors are used in combination with camera vision. The amount of information that has to be processed can overwhelm many processors. Solutions so far involved distributed processing, massively parallel processors, dedicated processors and mini computers. In most cases, these systems use specially designed processors, lacking standard interfacing, and as a result proprietary interface cards have to be built. This paper takes the alternate approach of designing a high performance controller using the parallel DSP systems, namely, the TMS320C40 processors with 275 MIPS and 50 MFLOPS. This controller processes data from a CCD camera which is focused onto a road segment containing a line that has suitable contrast with the road surface. The DSP based controller in a PC environment. Carries out the task of high level control while the low level servo control is assigned to dedicated motion controllers communicating with the DSP based controller through the PC bus. Results of image processing and timing requirements for various topologies are detailed.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years