Building cost-effective, low power Smart Grid / ‘Internet of Things’ (IoT) Modems

Published: Sat 12 Oct 2013
A blog entry by Sreedhar Tumma

Contributed by:

Sreedhar Tumma
Sr. Technical Marketing Manager
Cadence Design Systems, Inc

Sreedhar Tumma's Blog

Every smart appliance or machine connected to the Smart Grid will need a modem.The success for building cost-effective, low power Smart Grid / IoT modems depends on the implementation of the wired(e.g., G3 PLC) and/or wireless(e.g., 802.15.4g) PHY. With the Smart Grid/IoT connectivity protocols still evolving, implementing a “hardware(RTL) PHY” for these modems is a huge risk, if changes have to be made to the chip after the tape out.

The better option is to implement a “software PHY”. However, without a solution such as ConnX D2 (a very efficient 2-MAC DSP) based TIE optimized “Viterbi Decoder” and “Reed-Solomon Encoder/Decoder” from Cadence, it will be very challenging to build a very small, low power, high performance, programmable and scalable wired /Wireless software PHY.  The following table showcases the unique advantage of ConnX D2 based Smart Grid TIE acceleration package.

TIE Acceleration Benefit (Compared to C Reference Implementation)

FEC Algorithms Acceleration

Viterbi Decode K=7, coding rate of  ½


Viterbi Decode K=4, coding rate of  ½


Reed-Solomon (255,239) encode


Reed-Solomon (255,239) decode


There is a huge reduction in the number of cycles to run the required ‘computationally intensive’algorithms, when the Smart Grid TIE Acceleration package is used. This means, in addition to full software programmable capability, the final modem implementation will consume very less power and less memory (due to reduced code size). Also, new instructions can be easily added to the core DSP for accelerating algorithms for custom functionality and / or advanced security implementations.

Apart from running the PHY protocol, the ConnX D2 DSP has enough headroom for additional software tasks, providing possibilities for building multi-standard and hybrid (both wired and wireless) Smart Grid / IoT modems. Software stacks from our ecosystem partners are available for different Smart Grid / IoT applications.

Cadence also provides other silicon proven IP, and EDA tools for quickly building a complete Smart Grid / IoT SoCs, with minimal risk and fast time to market. Additionally, Smart Grid / IoT gateways can be implemented using the silicon proven Ethernet IP and LTE modem reference designs.

I’m attending the European Utility Week event and will be in Amsterdam from October 13th afternoon to October 17th.

If you need more details about our SmartGrid IP and its applicability for building your SmartGrid SOC(s), please email me at for scheduling a meeting.