Realization of two‐dimensional digital filters with powers‐of‐two coefficients

Abstract This paper aims at the simplification of operation and the reduction of hardware complexity and presents the construction of the two‐dimensional digital filter using powers‐of‐two coefficients. The proposed two‐dimensional digital filter is composed of a cascade connection of one‐dimensional digital filters with different frequency axis. The digital filter is structured as a cascade connection of the stopband‐forming filter and the passband‐compensating filter. The stopband‐forming filter is composed of the cascade connection of recursive running sum (RRS), and the passband‐compensating filter is constructed as a linear‐phase FIR or IIR type. The proposed method is especially effective for constructing a narrowband LPF. The zero coefficient sensitivity is realized by eliminating the multiplier. Another point is that the elliptic or polygonal two‐ dimensional filter can be approximated, which has been impossible by McClellan transform. The proposed method can realize more general two‐dimensional digital filters with a smaller hardware complexity, thereby eliminating the multiplier. Finally, it is verified by design examples that the hardware complexity is reduced in the proposed two‐dimensional digital filter, compared to the traditional method.