scispace - formally typeset
Search or ask a question

Showing papers on "Band-stop filter published in 2008"


Journal ArticleDOI
TL;DR: In this article, a compact ultra wideband (UWB) bandpass filter with notched band has been proposed and implemented, where three pairs of tapered defected ground structures (DGS) are formed to assign their transmission zeros towards the out of band signal, thereby suppressing the spurious passband.
Abstract: A compact ultra-wideband (UWB) bandpass filter (BPF) with notched band has been proposed and implemented in this letter. H-shaped slot is studied and adopted to tighten the coupling of inter-digital capacitor in order to improve the BPF's performance. Three pairs of tapered defected ground structures (DGS) are formed to assign their transmission zeros towards the out of band signal, thereby suppressing the spurious passband. Combining these two structures we obtain a small sized UWB BPF. Meander line slot is developed to reject the undesired wireless local-area network (WLAN) radio signals. An experimental UWB filter with notched band was fabricated with 35% less length as compared to an embedded open-circuited stub. The measured BPF insertion loss is less than 1.0 dB throughout the pass band of 2.8 to 10.8 GHz, the variation of group delay less than 0.20 ns in this band except for the notched band, and a wide stopband bandwidth with 20 dB attenuation up to at least 20.0 GHz.

152 citations


Journal ArticleDOI
TL;DR: In this article, the authors present several novel centrally loaded resonators and their applications to various types of bandpass filters and demonstrate these applications, four filters using the proposed resonators are implemented.
Abstract: This paper presents several novel centrally loaded resonators and their applications to various types of bandpass filters. Based on the theoretical analysis, it is found that the even- mode resonance of the proposed resonators can be conveniently controlled without affecting the responses at the odd-mode resonant frequencies. Benefiting from this feature, the resonator can be utilized to design not only harmonic-suppressed bandpass filters and dual-band bandpass filters but also tunable bandpass filters. The tunable filter offers a fixed passband and a tunable one. The center frequency of the upper passband can be electrically tuned, whereas the performance of the lower one is maintained constant. To demonstrate these applications, four filters using the proposed resonators are implemented. The experiments verify the theoretical predictions and simulations.

149 citations


Journal ArticleDOI
TL;DR: In this paper, a tri-band bandpass filter using short and open stubs loaded resonators is presented, the first and third passband frequencies can be flexibly controlled by tuning the lengths of the stubs, whereas the second passband frequency is fixed.
Abstract: A tri-band bandpass filter using short and open stubs loaded resonators is presented. The first and the third passband frequencies of the tri-band filter can be flexibly controlled by tuning the lengths of the stubs, whereas the second passband frequency is fixed. A tri-band filter has been implemented with four transmission zeros, the filter has good tri-passband performance at 1.57, 2.4, 3.5 GHz measured results agree well with simulated ones.

146 citations


Patent
10 Jun 2008
TL;DR: In this paper, a resonant switched power converter (LCLCL) with two pass band filters and a notch filter is presented. But the inductances of the preferred LCLCL tank circuit or other tank circuit with two-pass band filters are integrated into a single electrical component.
Abstract: A resonant switched power converter having switching frequency controlled in response to an output voltage thereof achieves over-current protection such as at start-up or under short circuit conditions using a resonant tank circuit which provides a notch filter in addition to a band pass filter. A additional band pass filter provided in the resonant tank circuit achieves increased power transfer to a load and reduced circulating resonant currents and conduction losses. The inductances of the preferred LCLCL tank circuit or other tank circuit with two pass band filters and a notch filter may be integrated into a single electrical component.

85 citations


Journal ArticleDOI
TL;DR: In this paper, a dual-wideband filter design implemented by stepped-impedance resonators, which involves the frequency mapping approach, is presented, and the dual-band filter can be divided into two parts: the wideband virtual passband filter and the narrowband virtual stopband filter, under the assumption that the common connecting lines serve as J- and K-inverters simultaneously.
Abstract: A dual-wideband filter design implemented by stepped-impedance resonators, which involves the frequency mapping approach, is presented in this paper. The dual-band filter can be divided into two parts: the wideband virtual passband filter and the narrowband virtual stopband filter. Both filters are designed by conventional synthesis methods, under the assumption that the common connecting lines serve as J- and K-inverters simultaneously. The basic building resonators formed by paralleling open- and shorting-stubs are implemented by unbalanced stepped-impedance resonators, exhibiting the desired resonating frequencies and susceptance slope parameters at these two bands. Two filters are tested to validate this design.

72 citations


Journal ArticleDOI
TL;DR: In this paper, a general procedure is described to design a sharp-rejection wideband bandstop filter by using interference of the signals propagating through two parallel transmission line segments having different electrical lengths and characteristic impedances.
Abstract: A general procedure is described to design a sharp-rejection wideband bandstop filter by using interference of the signals propagating through two parallel transmission line segments having different electrical lengths and characteristic impedances. Bandwidth and rejection level of the filters can be controlled by changing the impedances of the lines. A simple transmission line model is used for filter analysis. Design graphs are presented. Theoretical prediction is verified by fabricating two filters in microstrip technology. Good agreements is obtained among theoretical prediction, full-wave simulation and measurements.

72 citations


Journal ArticleDOI
TL;DR: Simulation results include: potentially 60-Gb/s non-return-to-zero (NRZ) data modulation and over 20-dB extinction ratio can be achieved by shifting the active ring by a 20 GHz resonance shift.
Abstract: A compact silicon coupled-ring modulator structure is proposed. Two rings are coupled to each other, and only one of these rings is actively driven and over-coupled to a waveguide, which enables high modulation speed. The resultant notch filter profile is steeper than that of the single ring and has exhibited a smaller resonance shift and lower driving electrical power. Simulation results include: (i) potentially 60-Gb/s non-return-to-zero (NRZ) data modulation and over 20-dB extinction ratio can be achieved by shifting the active ring by a 20 GHz resonance shift, (ii) the frequency chirp of the modulated signals can be adjusted by varying the coupling coefficient between the two rings, and (iii) dispersion tolerance at 0.5-dB power penalty is extended from 18 to 85 ps/nm, for a 40-Gb/s NRZ signal.

68 citations


Journal ArticleDOI
TL;DR: In this paper, a reconfigurable ultra-wideband (UWB) bandpass filter (BPF) with switchable notch for UWB system is presented, in which PIN diodes are used for electronic switching.
Abstract: A reconfigurable ultra-wideband (UWB) bandpass filter (BPF) with switchable notch for UWB system is presented. The UWB BPF is embedded with two identical switchable notch structures, in which PIN diodes are used for electronic switching. A bias circuit for UWB applications was investigated and designed to control the state of PIN diodes in order to activate or deactivate the notch without an affect on the response of the BPF. A demonstrator for this type of switchable notch UWB filter is designed and fabricated. Simulated and measured results are described.

63 citations


Journal ArticleDOI
TL;DR: A highly tunable deep notch filter realized in a liquid-crystal photonic-bandgap (LCPBG) fiber is demonstrated and a high degree of tuning of the spectral position of the deep notch is demonstrated.
Abstract: We demonstrate a highly tunable deep notch filter realized in a liquid-crystal photonic-bandgap (LCPBG) fiber. The filter is realized without inducing a long-period grating in the fiber but simply by filling a solid-core photonic-crystal fiber with a liquid crystal and exploiting avoided crossings within the bandgap of the LCPBG fiber. The filter is demonstrated experimentally and investigated using numerical simulations. A high degree of tuning of the spectral position of the deep notch is also demonstrated.

63 citations


Proceedings ArticleDOI
01 Nov 2008
TL;DR: The use of notch filters inside the loop in order to optimize the PLL performance is proposed; this approach is suitable both for single-phase and three-phase PLLs.
Abstract: Phase locked loop (PLL) algorithms for grid synchronization are a very important part of the control in most of the grid-connected power converters applications The performance of the PLL should not be much affected under distorted grid conditions: the presence of harmonics, unbalance, noise, etc in the inputs should not distort PLL measurements This paper presents an optimized design approach of PLLs, both for single-phase and three-phase systems The loop filter of the PLL sets its dynamic response; the loop filter should be tuned in order to achieve a correct tradeoff between transient response and harmonics/noise cancellation This paper proposes the use of notch filters inside the loop in order to optimize the PLL performance; this approach is suitable both for single-phase and three-phase PLLs Another novel interesting proposal of this paper is the implementation of the digitally controlled oscillator (DCO): the digital model of a sinusoidal oscillator is implemented, instead trigonometric functions This reduces the needed digital resources without reducing the performance This approach is specially useful for DSP-based control of power converters The proposed PLLs have been implemented and tested in a fixed point DSP (TI TMS320LF2407) and also in a floating point microprocessor (PowerPC of the dSpace DS1103) The systems have been tested with different distorted inputs in order to check the validity of the design approaches and good results have been obtained

63 citations


Journal ArticleDOI
TL;DR: In this article, the authors proposed a wave propagation notch for ultrawideband (UWB) filter applications, which is made of complementary split ring resonators (CSRRs), etched on the ground plane.
Abstract: Metamaterial resonator based wave propagation notch for ultrawideband (UWB) filter applications is proposed. The presented filter combines a conventional bandpass characteristic and negative permittivity metamaterial to establish a UWB response and extra wave propagation notch to reject the HiPerLAN interference, without compromise in performance and size. The negative permittivity metamaterial is made of complementary split ring resonators (CSRRs), etched on the ground plane. In addition a new method is proposed, demonstrating a significant improvement in the matching between the CSRRs and the host transmission line. The measured results show that the filter has an insertion loss less than 1 dB and bandwidth of 8.4 GHz with 22 dB rejection at 5.4 GHz.

Journal ArticleDOI
TL;DR: The key feature of this technique is that a photonics microwave delay-line filter with arbitrary bandpass response can be realized with only positive taps via nonuniform tap spacing.
Abstract: A new technique to implement a photonic microwave delay-line filter based on nonuniform tap spacing with arbitrary bandpass response is proposed and experimentally demonstrated. Being different from a regular photonic microwave delay-line filter where the taps are uniformly spaced, the proposed filter in this paper has nonuniformly-spaced taps. The key feature of this technique is that a photonics microwave delay-line filter with arbitrary bandpass response can be realized with only positive taps via nonuniform tap spacing. The use of the proposed technique to implement a flat-top bandpass filter is experimentally demonstrated.

Journal ArticleDOI
TL;DR: In this article, a microwave photonic filter structure that realizes both a multitap, flat-top radio-frequency bandpass filter and bipolar taps, while also exhibiting low-noise operation, is presented.
Abstract: A new microwave photonic filter structure that realizes both a multitap, flat-top radio-frequency bandpass filter and bipolar taps, while also exhibiting low-noise operation, is presented. It is based on using a phase-modulated laser signal propagating through a novel sinusoidal group delay grating, which induces tailored phase shifts to the carrier and sidebands. The filter integrates tap weighting and delays simultaneously in one unit, which enables multiple-tap low-noise signal processing together with negative coefficients. Experimental results demonstrate the realization of a flat-top bandpass filter response with 7.8-GHz free spectral range and more than 45-dB rejection ratio. Extensions to this concept by connecting additional sinusoidal group delay gratings in cascade, to provide enhanced signal processing functions, are also described.

Patent
20 Feb 2008
TL;DR: In this article, an amplifier with integrated filter (e.g., an LNA) is described, which includes a gain stage, a filter stage, and a buffer stage.
Abstract: An amplifier with integrated filter (e.g., an LNA) is described. In one design, the amplifier may include a gain stage, a filter stage, and a buffer stage. The gain stage may provide signal amplification for an input signal. The filter stage may provide filtering for the input signal. The buffer stage may buffer a filtered signal from the filter stage. The amplifier may further include a second filter stage and a second buffer stage. The second filter stage may provide additional filtering for the input signal. The second buffer stage may buffer a second filtered signal from the second filter stage. All of the stages may be stacked and coupled between a supply voltage and circuit ground. The filter stage(s) may implement an elliptical lowpass filter. Each filter stage may include an inductor and a capacitor coupled in parallel and forming a resonator tank to attenuate interfering signals.

Journal ArticleDOI
TL;DR: In this paper, a compact dual-mode filter is proposed by using rectangle structure and several attenuation poles in the stopband are realized to improve the selectivity of the proposed bandpass filter.
Abstract: A compact dual-mode filter is proposed by using rectangle structure. The filter has the characteristics of compact structure, low insertion loss and so on. Several attenuation poles in the stopband are realized to improve the selectivity of the proposed bandpass filter. The experimented results were in good agreement with simulated results.

Journal ArticleDOI
TL;DR: In this paper, a sharp-rejection bandstop filter (BSF) with wide rejection bandwidth was proposed to control the rejection bandwidth and the level of rejection by the characteristic impedances of the transmission lines.
Abstract: In this letter, a novel transmission line configuration has been proposed to design a sharp-rejection, bandstop filter (BSF) with wide rejection bandwidth. The rejection bandwidth and the level of rejection are controlled by the characteristic impedances of the transmission lines. Design equations are obtained by using a lossless transmission line model. The proposed design has been verified in microstrip line by fabricating a prototype BSF of -20 dB fractional bandwidth of 100% at a stopband center frequency f0 = 1.5 GHz. The filter structure is simple and easy to fabricate.

Journal ArticleDOI
TL;DR: In this article, a novel wideband bandpass filter using the asymmetric stepped-impedance resonator (SIR) with one step discontinuity is designed and implemented to achieve characteristics of low loss, wide stopband and very high passband selectivity, simultaneously.
Abstract: In this letter, a novel compact wideband bandpass filter using the asymmetric stepped-impedance resonator (SIR) with one step discontinuity is designed and implemented to achieve characteristics of low loss, wide stopband and very high passband selectivity, simultaneously. The first two resonant modes of the asymmetric SIR are coupled together and applied to create a wide passband. The design procedure is discussed in detail. The proposed filter at center frequency f0 of 4 GHz has very good measured characteristics including a low insertion loss of 0.5 plusmn 0.3 dB, the bandwidth of 2.9-5.3 GHz, sharp rejection due to two transmission zeros in the passband edge. Experimental results of the fabricated filter show a good agreement with the predict results.

Patent
12 Mar 2008
TL;DR: In this paper, the authors describe techniques for reducing adverse effects of TX signal leakage in a full-duplex, wireless communication device using a notch filter to reject TX signals in a signal processed in the RX path of the device.
Abstract: This disclosure describes techniques for reducing adverse effects of TX signal leakage in a full-duplex, wireless communication device. The techniques make use of a notch filter to reject TX signal leakage in a signal processed in the RX path of the wireless communication device. The notch filter may be constructed as a complex notch filter using passive resistor and capacitor components to produce a notch frequency that attenuates TX signal leakage components in a desired signal. The notch filter may be applied to a down-converted, baseband signal produced by a passive mixer.

Journal ArticleDOI
TL;DR: A first-order all-pass filter with electronic tuning properties is presented that is cascadable, has small sensitivities, and suitable for monolithic integration, and can also operate at high frequencies.
Abstract: A first-order all-pass filter (APF) with electronic tuning properties is presented The filter consists of only active components and a single-grounded capacitor The circuit is cascadable, has small sensitivities, and suitable for monolithic integration, and it can also operate at high frequencies

Journal ArticleDOI
TL;DR: In this paper, a compact microstrip bandpass filter with extended stopband is proposed using both quarter-wavelength (lambda/4) stepped-impedance resonators and bandstop embedded resonators.
Abstract: Novel compact microstrip bandpass filters (BPFs) with extended stopband are proposed using both quarter-wavelength (lambda/4) stepped-impedance resonators and bandstop embedded resonators. First, by properly designing the impedance and length ratios of the stepped-impedance resonators, the developed filter may be made compact and its spurious harmonics may be pushed to the higher frequency region. Next, by suitably designing the bandstop structure so as to suppress the lower spurious harmonics of stepped-impedance resonators and then embedding the bandstop structure into the lambda/4 resonators, one may realize the BPFs with wideband spurious suppression. In particular, by connecting the bandstop embedded resonators to the input/output ports, a compact fourth-order BPF of dimension 0.089 lambdag times 0.27 lambdag is implemented and its stopband is extended up to 8.25 f 0 with an adequate rejection of greater than 32.49 dB, where f 0 is the passband center frequency and lambdag is the microstrip guided wavelength at f 0.

Proceedings ArticleDOI
Ahmad Mirzaei1, Hooman Darabi1
01 Feb 2008
TL;DR: A filtering technique to attenuate the receive-band noise enables a 65-nm CMOS WCDMA transmitter to achieve an output noise level of -160 dBc/Hz at 80-MHz offset, while dissipating 65 mW.
Abstract: In a WCDMA FDD system, since the transmitter and receiver operate concurrently, the receiver is plagued by the transmitter leakage due to finite isolation of antenna duplexer. As a consequence, the transmitter noise at the receive band degrades the sensitivity, unless the noise is further attenuated before reaching the receiver. Due to the modest Q of on-chip inductors, typically the use of a costly SAW filter placed before the PA is inevitable. On the other hand, the external filter may be eliminated through sufficiently lowering the transmitter noise for any given duplexer. However, given the power-noise trade off, in all previous designs due to the lack of an on-chip filtering mechanism, meeting the stringent noise requirement has resulted in an excessive transmitter power dissipation. To address these issues, a feedback-based filtering technique to suppress the receive-band noise with negligible area or power penalty is presented. Stability analysis reveals that with practical transmitter gain distribution, optimum component sizes, and for a typical required noise suppression, using a simple first- or second-order RC LPF, the feedback remains stable and no additional compensation is required.

Journal ArticleDOI
TL;DR: A novel method for the implementation of a tunable multi-channel notch filter based on a thermally induced phase-shift phase-only sampled fiber Bragg grating is proposed and offers the potential applications to the multiwavelength fiber laser and multi- channel all optical logic devices.
Abstract: We propose a novel method for the implementation of a tunable multi-channel notch filter based on a thermally induced phase-shift phase-only sampled fiber Bragg grating (FBG). The proposed method is numerically and experimentally demonstrated. A 51-channel notch filter with a bandwidth (FWHM) of 0.026 nm and a tuning range of 0.6 nm has been achieved. This proposed technique offers the potential applications to the multiwavelength fiber laser and multi-channel all optical logic devices.

Proceedings ArticleDOI
15 Jun 2008
TL;DR: In this article, the authors presented the first suspended 3-pole RF MEMS tunable filter with a frequency coverage of 1.6-2.4 GHz, which is the best report at this frequency range using any planar technology.
Abstract: This paper presents the first suspended 3-pole RF MEMS tunable filter with a frequency coverage of 1.6-2.4 GHz. The suspended topology is chosen to result in a high-Q resonator, which is essential for a low-loss 3-pole filter. The filter results in an insertion loss of 1.34-3.03 dB over the tuning range and a 3-dB bandwidth of 201-279 MHz. This design results in a tunable Q u of 50-150 over the frequency range, which is to our knowledge, the best report at this frequency range using any planar technology.

Journal ArticleDOI
TL;DR: Design and development of digital FIR equiripple notch filter is designed and applied to the ECG signal containing power line noise which clearly indicates the reduction of the power line interference in theECG signal.
Abstract: Filtering of power line interference is very meaningful in the measurement of biomedical events recording, particularly in the case of recording signals as weak as the ECG. The available filters for power line interference either need a reference channel or regard the frequency as fixed 50/60Hz. Methods of noise reduction have decisive influence on performance of all electro-cardio-graphic (ECG) signal processing systems. This work deals with problems of power line interference reduction. In the literature of the last twenty years several solutions of removal of power line interference on electrocardiogram (ECG) signals can be found. Some analogue and digital approaches to this problem are presented and its properties, advantages and disadvantages are shown. Present paper deals with design and development of digital FIR equiripple filter. The basic ECG has the frequency range from. 5Hz to 100Hz. Artifacts plays the vital role in the processing of the ECG signal. It becomes difficult for the Specialist to diagnose the diseases if the artifacts are present in the ECG signal. In the present work notch filter is designed and applied to the ECG signal containing power line noise. Complete design is performed with FDA tool in the Matlab. The equiripple notch filter designed is having higher order due to which increase in the computational complexity observed. For accessing real time ECG the related instrumentation has been developed in the laboratory. The result shows the ECG signal before filtering and after filtering with their frequency spectrums which clearly indicates the reduction of the power line interference in the ECG signal.

Patent
11 Sep 2008
TL;DR: In this article, the frequency of a notch of a digital-to-analog conversion block is related to the value of the delay from the delay block, and summing circuitry sums the radiofrequency signals.
Abstract: An electronic device, includes sigma-delta modulation circuit to operate with a clock signal and having output circuitry to deliver a digital data signal. First circuitry delivers a radiofrequency transposition signal. A notch filter includes radiofrequency digital-to-analog conversion blocks, having first input circuitry coupled to the output circuitry. Second input circuitry receives the radiofrequency transposition signal. Second output circuitry delivers a radiofrequency analog signal. Digital delay circuitry is controlled by the clock signal and includes a delay block between the two first input circuits. The frequency of a notch of the notch filter is related to the value of the delay from the delay block. Summation circuitry sums the radiofrequency signals.

Journal ArticleDOI
TL;DR: In this article, three voltage-mode universal biquadratic filters with single input and five outputs have been proposed, which can simultaneously realize voltagemode lowpass (LP), bandpass (BP), highpass (HP), bandstop (BS) and allpass (AP) responses employing all grounded passive components.
Abstract: Three new voltage-mode universal biquadratic filters configuration are proposed. The first proposed high-input impedance universal filter with single input and five outputs, which can simultaneously realize voltage-mode lowpass (LP), bandpass (BP), highpass (HP), bandstop (BS) and allpass (AP) filter responses employing all grounded passive components. The second proposed high-input impedance universal filter with three input and single output, which also can realize all the standard filter functions without requiring any inverting input voltage signal. The third proposed universal filter with three inputs and five outputs, which can be used as either a three-input single-output or a two-input five-output universal filter. Moreover, each of the proposed circuits still enjoys (i) the employment of only grounded capacitors, and (ii) no requirement with the component choice conditions to realize specific filtering functions.

Journal ArticleDOI
TL;DR: In this article, the adaptive notch filter is used for attitude control of a flexible launch vehicle using adaptive notch filtering with real-time control and an experimental ground model is developed to verify the stability of the adaptive control technique based upon an adaptive filter.

Patent
04 Jun 2008
TL;DR: In this article, a cascaded multi-resolution filter bank (CMCF) was proposed to improve the quality of the audio signal by switching to an additional extension filter bank during transient or fast changing audio signal sections.
Abstract: Perceptual audio codecs make use of filter banks and MDCT in order to achieve a compact representation of the audio signal, by removing redundancy and irrelevancy from the original audio signal. During quasi-stationary parts of the audio signal a high frequency resolution of the filter bank is advantageous in order to achieve a high coding gain, but this high frequency resolution is coupled to a coarse temporal resolution that becomes a problem during transient signal parts by producing audible pre-echo effects. The invention achieves improved coding/decoding quality by applying on top of the output of a first filter bank a second non-uniform filter bank, i.e. a cascaded MDCT. The inventive codec uses switching to an additional extension filter bank (or multi-resolution filter bank) in order to re-group the time-frequency representation during transient or fast changing audio signal sections. By applying a corresponding switching control, pre-echo effects are avoided and a high coding gain and a low coding delay are achieved.

Journal ArticleDOI
TL;DR: In this paper, an improved hairpinline microstrip narrowband bandpass filter with via ground holes is presented, which reduces the size of the filter by 35% as compared to the conventional design.
Abstract: In this paper, we present a novel improved hairpinline microstrip narrowband bandpass filter with via ground holes. The new filter design methodology is derived from conventional hairpinline filter design. This design methodology incorporates use of λ/8 resonators, thereby reducing the size of the filter by 35% as compared to the conventional design. An analysis is presented to show the effects of tap point height and microstrip width on fundamental parameters of filter and subsequent relationships are developed. Through use of via ground holes and a wider microstrip line for resonators, 3 dB Fractional Bandwidth (FBW) less than 2%, Insertion Loss (IL) less than 1.6 dB and Return Loss (RL) better than 40 dB is achieved with midband center frequency 1 GHz. Spurious response suppression is achieved till 3f0. Robustness of this design approach is demonstrated by designing filters on two more substrates having er 2.17 and 9.2. As low as 0.48% FBW was achieved by using different substrates. The design approach is successfully tested for center frequency upto 2 GHz beyond which folding the resonator becomes practically difficult. Finally, a bandpass filter is designed with this design methodology and fabricated using FR4 substrate. S-parameter measurements show a good agreement with the simulated results.

Journal ArticleDOI
TL;DR: Results clearly indicate that there is noise reduction in the ECG signal.
Abstract: Coronary heart disease (CHD) is the leading cause of death for both men and women in the all over the world and India too. CHD is caused by a narrowing of the coronary arteries that supply blood to the heart, and often results in a heart attack. Each year, about millions man kind suffers from heart attack. About maximum of those heart attacks are fatal. About half of those deaths occur within 1 hour of the start of symptoms and before the person reaches the hospital. A heart attack is a medical emergency. Hospitalization is required and possibly intensive care. ECG signal is very important signal in the cardiology. Different artifacts are the reason behind the corruption of the signal care should be taken to avoid the interferences in the ECG. The work is in that direction. Present paper deals with the design of the FIR filter using rectangular window. Basically three filters are designed namely low pass filter high pass filter and notch filter. All the filters are cascaded also. These filters are applied on the ECG signal in the real time manner. For the real time application the 711B add-on card has been used. Results clearly indicate that there is noise reduction in the ECG signal. A Comparative Results are Provided in the paper.