Digital seems to be the buzzword in today’s electronic experience—be it digital television, camera, phone, video or audio. Have you ever wondered why the word ‘digital’ is so appealing? What is the unique selling point of these products? The answer is simple—significant improvement of experience without distortion. How? The answer is—signals today are being processed digitally through digital signal processing or DSP.
“DSP has revolutionised the way we look at new electronic and telecom products
in terms of size, power and efficiency. We use a myriad of devices today, all of which embed a large number of DSPs,” says Manoj Misra, director and head-DSP, FPGA & ASIC Practice, Hughes Systique Corporation.
If hours and hours of signal analysis to process, amplify and appropriate interpretation attracts you then it’s an industry worth considering for career development.
Catch a glimpse…
The term DSP is used to describe signal processing in digital domain either in hardware or in software. In fact, all digital devices perform signal process-ing—be it a mobile, radar, ECG, MRI machine, TV, camera, microwave oven, washing machine, car, satellite or an airplane—the list is very long.
India is a developing economy with embedded, IT, software industries that are growing at a modest rate of 9-11 per cent per annum. The captive needs and potential growth of business is luring many Indian companies/investors as well as foreign investors/companies to invest in new niche areas like telecom, communication, defence, space, medical instrumentation, consumer electronics, etc. This has resulted in many centers of excellence focusing on activities related to DSP applications. Some of the key potential areas include defence, telecom, multimedia, medical instrumentation, low-cost smart devices, space and aviation industry, consumer electronics, auto industry and safety products.
NASSCOM has projected DSP as a career with high growth prospects. DSP programming and technology is mathematics-intensive. Indian graduates may stand to have an edge over others as they tend to be skilled in number crunching. “Though there are quite a few experienced DSP engineers commanding the top positions in the industry, the gap in supply and demand of skilled DSP staff shows no sign of easing, and with ever widening applications of DSP, there is no better time to embrace and master this technology,” opines C.P. Ravikumar, Texas Instruments.
The recruitment trend for this sector further confirms his statement. Larger players like Samsung, Nokia, Motorola and Texas Instruments, as well as a host of small and medium design solution providers like Ittium, Hughes Systique and AppliedMicro, offer opportunities in DSP. Even auto companies like Ashok Leyland, Tata Motors, Mahindras, Bajaj and Maruti, and healthcare companies like Philips and Siemens offer exciting career options in signal processing. Companies like Wipro and Mindtree that invest in product development, also require DSP professionals.
What your pocket says
Let’s turn to ‘money matters.’ It won’t be an exaggeration to suggest that this field offers enough provisions for learning as well as earning. This industry is typically at the higher end of the value chain and hence the salary and rewards are at above average levels of the industry.
The pay is quite good even for freshers.
The high demand for competent staff in DSP segment creates several opportunities for aspirants. The starting salary for a fresher is typically between Rs 300,000 to Rs 500,000 per annum with impressive year to year salary hikes. As an engineer, you may choose to continue in the area of technology, be a part of the techno-commercial team or move to the business development aspect of the service. As stated by Ravikumar, “Under the technical career path, an individual who starts off as a DSP engineer can grow to the highest level of a chief technical officer (CTO). And on the managerial career path, he/she can grow to the level of a business line head.”
Getting the job signal….
Who can get a job signal in DSP? Is there any scope for freshers? Any engineer with a specialisation in either electronics and communication engineering, or computer science, or electrical engineering, can enter this field.
“There is definitely strong need for fresh engineering talent to come into the DSP industry. People aspiring to build a career in this field need to be strong in fundamental principles in one or more areas of circuit design, signal processing algorithms, embedded software development, application software development and system board design,” says Srini Rajam, chairman and CEO, Ittiam.
Further focusing on the bright prospects in India for DSP technology and applications, Rajam divides all available jobs in this sector under three broad categories—DSP processor chip design, software development on DSP and hardware and system design using DSP.
If you like to ‘play’ with gadgets, you can get involved in designing them. A good student of mathematics can delve deep into the mathematics of signal processing. If, on the other hand, you are research-oriented, you can work to develop next-generation tools and products for automotive, health-care, communications, computing and defence electronics, algorithms, design techniques, production tools or software tools. There is in fact an option to explore special algorithms for encoding, compression or encryption. You can even participate in the ‘standards evolution process’ that could be used to design and develop future products.
“Though there are quite a few experienced DSP engineers commanding the top positions in the industry, the gap in supply and demand of skilled DSP staff shows no sign of easing, and with ever widening applications of DSP, there is no better time to embrace and master this technology.”
—C.P. Ravikumar, Texas Instruments
hough there are quite a few experienced DSP engineers commanding the top positions in the industry, the gap in supply and demand of skilled DSP staff shows no sign of easing, and with ever widening applications of DSP, there is no better time to embrace and master this technology.
– C.P. RaviKumar, Texas Instruments
There is also room for traditional electronic design, synthesis and analytical skills. You can explore new ASIC or FPGA designs, VLSI tools and EDA tools. An interest in science can get you into next-generation applications in oil, space, under-sea exploration, whereas an inclination towards signal processing can get you into defense electronics.
How to get started?
It is hard to get excited about a field that you know little about. Equally, it is difficult to delve into it unless you know the purpose or the ‘big picture.’ Let’s have a look at the ‘big picture’ of DSP. Digital signal process manipulates real world signals—analogue voice, music, video, engine speed—to numerical values by using a digital signal processor. Analysis is performed in digital form because once a signal has been reduced to simple numbers, its components can be isolated, analysed and rearranged more easily than in the analogue form.
Eventually, when the DSP is done, the digital data is converted into analogue data with improved quality. For example, a digital signal processor can filter noise from a signal, remove interference, amplify some frequencies and suppress others, encrypt information, or analyse a complex waveform into its spectral components.
Digital signal processors are usually implemented in a single chip or even as part of an IC and embedded in every digital product. Today, there is in fact an overlap between the role of a traditional microprocessor and digital signal processors. In fact, the main differences lie in the internal chip architecture, with DSP particularly optimised for high-speed, high-accuracy manipulations.
Firms, during recruitment, look at a combination of consistent academic record, deep understanding of subject matter and soft skills. Though the Indian academia is churning thousands of engineers per year, there is a significant gap between the need of industry and what a fresher brings to the table. According to Ravi Kumar, of the (over) 450,000 technical graduates churned out every year from engineering institutes, only around 25 per cent are employable. Even these engineers are not really ‘industry ready.’
In order to reduce the gestation period of a fresher, there is a need for training and investment. They are not productive from day one. Stands to reason therefore that when you are looking at honing your skills for a job, you need to know what’s in demand. Let’s therefore focus on the industry expectations; on some of the basic things that your potential employer may be looking at, when he/she decides to interview you.
“Depending on whom you work for, you need different competencies. Signal processing requires a sound knowledge of both analogue and digital signal processing. There is maths, algorithms, implementation, tools, system design and so on,” says, Prof S. Sadgopan, founder director, IIT-Bangalore.
As an aspiring professional, you should start from the base level. Try to understand what makes DSP preferable to analogue signal processing and also its limitations. For developing better understanding, brush up the nitty-gritty of microcontrollers before jumping into DSP. Your key skill sets should include knowledge of microcontroller architecture, specially advanced ones like ARM, PPC, MIPS
There is definitely strong need for fresh engineering talent to come into the DSP industry. People aspiring to build a career in this field need to be strong in fundamental principles in one or more areas of circuit design, signal processing algorithms, embedded software development, application software development and system board design.
—Srini Rajam,Chairman and CEO, Ittiam
for SOC (system on chips); testing protocols and tools; networking and instrumentation procedures and protocols; and also a sound knowledge about the basics of analogue and digital designs. Try developing an idea about handshaking signals developed for communication channels, interface cables for various common interface standards such as RS-232-C, RS-485, RS-422 and RS-423. Know the processors to understand the processing. You need to have intimate knowledge of processor architectures—pipelining, VLIW/multi processing, memory systems and hardware-software interfaces. In fact, along with DSP programming you may need to participate in architecture specification.
As Mishra says, “A fresh graduate in the industry is expected to have basic knowledge of DSP architecture and a strong programming skills and simulation/testing fundamentals background. A good knowledge of algorithm development, system modeling and niche technology areas like communication is always an added advantage. Based on the individual potential, a fresher can take up roles in system modeling and simulation, DSP application design and coding and optimisation. The competency requirement for this field is to develop algorithms and applications based on DSPs (both real time and non-real time), good programming skills and understanding of DSP architectures. Most of the engineers available today have background in software engineering and they lack the combination of skills required to become a DSP engineer.”
Hold your feet tight
A DSP-based application development needs a mix of competitive skill sets that comprises system modeling, algorithm development, application coding, integration, testing and validation. Typically, a team comprises engineers with different experience levels with various skill sets. Today, there are additional technologies used for signal processing including DSPs, powerful general-purpose microprocessors, field-programmable gate arrays (FPGAs).
For a successful career in DSP-related applications, an engineer should have a sound understanding of the DSP architectures and coding skills (Matlab, Assembly, C programming and scripting). Apart from these basic skill sets an experienced DSP engineer needs to develop requisite knowledge and understanding of processors architecture like superscalar, VLES, VLIW, SIMD and concepts like branching, threading, context switching, multithreading etc. The need for real-time system design is increasing with newer technologies and applications coming in the market. This requires an understanding of real-time operating systems, memory management, BUS standards, etc. System integration and testing is another area in DSP, which requires a good understanding of the overall system design and validation needs. This requires test scripts writing and handling testing equipment like logic analysers, oscilloscopes, spectrum analysers, etc. A hands-on experience on DSPs from companies like TI, Analog Devices, Freescale, Infenion, etc, definitely helps in the long run.
Start with the design for DSP applications. Like any other design, a DSP design also goes through a number of stages and iteration before the final product is out. However, fundamentally, the process may be represented in three steps—algorithm development and design, software coding and hardware implementation.
In order to get started with DSP software development, you need a number of basic tools like basic text editor, assembler, linker, dubug environment, downloader and hex conversion utility. These allow the conversion of program to a form understandable to the DSP and then it is downloaded to the target device. You have to be aware of assembly-level programming and the C language, and even C++.
A DSP professional is expected to be well-versed with real-time programming, signal processing algorithms and time constraints. Further, you need to know how a DSP algorithm gets converted from a program written on paper to a working solution incorporating both hardware and software and other algorithmic issues like filter design and FFT design.
A complete package of tools like Matlab, system view, etc, may be useful as they allow an engineer to place functional blocks representing algorithmic operation into a block diagram of the system. Even they can be redefined according to a specific DSP requirement.
Delve a little deeper, you’ll find that most of the design time involved in developing a DSP-based product is spent in sorting out small issues like AC-coupling input, auto leveling output, or figuring out how to compute a square root. A DSP engineer should learn how to solve these petty problems by a careful choice of DSP algorithms related to logical operation, arithmetic operation, filtering and liner scaling algorithms.
To do this you must be able to understand digital filter design, spectral analysis, specialist applications like signal averaging, and automatic level control along with the general-purpose algorithms. Put an emphasis on numerical methods like fast fourier transform (FFT) and the relationship between time and frequency domain representation.
Basically, you are expected to understand the theory behind the working of these algorithms.
Depending on whom you work for, you will need different competencies. Signal processing requires a sound knowledge with both analogue and digital signal processing. There is maths, algorithms, implementation, tools, system design and so on.
—Prof S. Sadgopan, Founder Director, IIIT- Bangalore
The next thing you need to know is the basic hardware and its usage. Standard hardware can be divided into functional blocks, for example—DSP clocks, external memory, expansion interface, PCI interface, JTAG emulation, programmable logic, audio interface, power supplies, voltage supervision, user option, LED indicators and so on. Try to get an overview of each of them. Your realistic knowledge of electronics circuit will be useful at this stage. In addition, the preliminary knowledge of ARM series processor, RTC, memory chips, video standards (MPEG, H.264, VC-1) and video processing wide application porting, FIR and IIR filters, linear time invariant systems, algorithms development and Matlab experience may be nice.
Most manufacturers of DSP devices offer a low-cost development board that is intended to be used for the basic evaluation of the technology. It is usually free standing and connects to the PC via a slow data link—a serial or parallel connection. It comes along with a comprehensive set of software tools for assembling, linking, debugging and downloading code.
In fact, you may consider continuing your final year project with such a ‘starter kit.’ This is all that is needed to begin experimenting and developing the device. Major manufacturing firms across the world also hold informative DSP seminars for beginners.
Know the real systems
On reaching this point, your next challenge will be to explore how to provide solutions for a real device. You can learn the chip to ship of this process only after completing a proper project. “Augmenting the university curriculum with good industrial training/projects would be an excellent way to prepare oneself for the career,” Says Rajam.
Nearly all our institutes, barring a handful, are woefully inadequate in providing students with such opportunities. But, industry is always ready to help a deserving candidate. Ravikumar, Technical Director-University Relation, Texas Instruments, explains that their extensive ‘internship programme’ provides enough learning opportunity to a student. The only thing to do from the students’ end is to complete the groundwork about DSP by using the steps we have discussed earlier.
“We also have a strong internship programme, and a lot of times interns join us after completing their term. DSP engineers are expected to have a good background in the fundamental courses covered during under graduation (E&C, EE & CS) and post-graduation (M.Tech, PhD) exhaustively. The person interested in joining DSP field should have a strong background in mathematics, electronics and computer engineering along with analytical skill sets like algorithm development, problem definition and solution. A good understanding of system modeling and simulation and programming skills (Mat lab/Assembly/C/C++) is necessary for an aspirant,” says C.P. Ravi Kumar, technical director, university relations, Texas Instruments.
A DSP application industry may also turn out to be your favorite destination. For example, the telecom sector is likely to see tremendous growth in India’s rural and semi-urban areas in the years to come. So, involvement in a wireless DSP implementation project in CDMA/WCDMA/LTE can go a long way in providing an edge over your competitors. Bear in mind, no matter which type of application is involved in the project, it will no doubt touch upon areas like—DSP software development, participation in architecture specification, design, coding and module/subsystem testing. A good understanding of the network transmission hierarchy may prove useful.
Last but not the least
If you feel that you may lag behind due to lack of practical exposure then a strategically chosen course may be the solution. I emphasise on the word ‘strategically’ because it decides whether you will get a job or your money will go down the drain. So, before choosing the course, judge the reputation of the institute, the certification system, the industry accreditation and the course curriculum.
Ultimately, everyone wants a best fit. Therefore the first step is to be clear about your goals. Then you can go ahead and make that call!
The author is a consultant—editorial, industry & academia interface at EFY