A novel design of sharp transition FIR filter for digital beamforming

Design of Sparse Uniform Linear Array Beamformer using Modified FRM Structure for Varied Applications

“…The transfer function of the ModFRM filter can be expressed as [23]: (5) where H a,q (z L ) is the q th DFT modulated prototype filter interpolated by L. Equation ( 5) can be rewritten as: (6) where, Both the even BES-FB or odd BES-FB can be used to determine the frequency response of the ModFRM filter around the transition band. Accordingly, the masking filter design may be done in two ways as follows [23]:…”

“…Among the various techniques, array beamformer synthesis is closely associated with the design of digital finite-impulse-response (FIR) filters, in which the tapped delay line is transformed by spatial delay, and the filter length is proportional to the number of antennas. The Uniform Linear Array (ULA) is the most widely used array geometry because of its simplicity, superior directivity, and realization of the narrow beamwidth in a given direction [5,6]. In the ULA beamformer, the spatially sampled sequences from each sensor are linearly combined in the same way the temporally sampled data are linearly combined by an FIR filter [7].…”

“…There-forth, sparse arrays have received much attention from system designers to save costs [8][9][10][11][12]. In sparse array beamforming, interpolation techniques are frequently used [5,[13][14][15]. FIR filter design techniques, such as Frequency response masking (FRM) proposed by Lim [16,17] and interpolated FIR [18], have lately been investigated to see if they may be used in array processing [19][20][21].…”

Sharp Transition Multiband Filter in Speech Processing Scheme for Hearing Impaired

“…A serious disadvantage of FIR filters is its complexity, which becomes acute in sharp trasition filters. A computationally efficient design technique for synthesis of sharp transition FIR filters is Interpolated FIR filter which is a FIR-FIR filter cascade and employs sparse filter and an interpolator filter (Neuvo et al, 1987;Jovanovic-Dolecek and Diaz-Carmona, 2002;Yang and Lian, 2002;Gudino et al, 2008a;2008b;2008c). The interpolation designs introduce large group delays.…”

Null steering based beamforming techniques

“…The similarity between uniform linear array (ULA) beamformer and temporal finite impulse response (FIR) filter makes filter design methods applicable for beampattern synthesis. As depicted in [23,24], the impulse response of an FIR filter is directly employed as the array coefficients. However, the designed beamformers are data independent.…”