Low-power hybrid structure of digital matched filters for direct sequence spread spectrum systems

The paper presents a low-power structure of digital matched filters (DMFs), which is proposed for direct sequence spread spectrum systems. Traditionally, low-power approaches for DMFs are based on either the transposed-form structure or the direct-form one. A new hybrid structure that employs the direct-form structure for local addition and the transposed-form structure for global addition is used to take advantage of both structures. For a 128-tap DMF, the proposed DMF that processes 32 addends a cycle consumes 46% less power at the expense of 6% area overhead as compared to the state-of-the-art low-power DMF (Liou, M. and Chiueh, T., IEEE J. Solid-State Circuits, vol.31, p.933-43, 2001).