Low-Power ACSU Design for Trellis Coded Modulation (TCM) Decoder

  • N. N. Thune
  • S. L. Haridas
Conference paper
Part of the Smart Innovation, Systems and Technologies book series (SIST, volume 106)


Nowadays large constraint length convolution encoders/decoders are used for better output performance. TCM Decoder used for satellite communication is having large constraint length greater than or equal to 7. For a large constraint length number of the states is also large this will lead to large power dissipation and complexity of the system. In TCM decoder, VD is one of the important parts. In VD to find an optimal path out of existing paths T-algorithm is used, this process limits the clock speed due to large calculations. So it is essential to purge some part of ACSU which will reduce complexity as well as power dissipation. In this paper, the efficient architecture of the ACSU unit is proposed which is based on modified pre-computation architecture. New suggested design provides reduced complexity and power consumption in comparison with existing T-algorithm. This design shows acceptable decoding performance with negligible calculations.


TCM (Trellis coded modulation VD (Viterbi decider) PM (Path metric) PSK (Phase-shift keying) TMU (Transition metric unit) ACSU (Add-compare-select unit) 


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Copyright information

© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.Electronics EngineeringRTM Nagpur University, GHRCENagpurIndia
  2. 2.Electronics & CommunicationRTM Nagpur University, GHRCENagpurIndia

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