CEL Highlights How To Reduce Power Consumption With Superior Wireless And Testing

Reducing power consumption for wireless IoT designs seems to be every engineer’s challenge. Beyond considering the core technology, duty cycle, operating modes, and the application itself, developers should also focus on the wireless performance to help optimize their device and system for low power operation. Fine-tuning the wireless performance can have a measurable and sometimes significant impact on an end-product and system’s energy consumption. Here are a handful of items to consider and examine:

Minimizing the On-Air Time

Achieving higher throughput…get on and off the air quickly (even for low data applications)

Extend your link budget through higher radiated power (not Tx Power), antenna gain, and Rx sensitivity

Enhance your EVM to achieve fewer corrupt packets and retries…minimize gain and phase mismatch, reduce clock error, decrease phase noise with a higher quality XTAL, optimize PA performance

Reducing Tx Power

A more efficient antenna that radiates at a higher level will allow you to reduce the Tx power when you are within range of the target device. Inefficient antennas have less radiated power; therefore, they need to Tx at a higher level to achieve the same radiated power and thus consume more energy

Optimizing the layout and location of antenna

CEL works with customers to position the radio so the signal can penetrate the enclosure and radiate as strong as possible

Antenna Performance

Omni directional performance…increase the chance of direct line-of-site connection

Match and tune for higher efficiency

Testing

TRP of final product(s)…Understanding the radiation pattern of your end-product is critical…comparing it to a chip or module is only a reference point

iPerf…Measure the health and performance of your product/system

Field Testing…Testing in the intended environment is a must

EXAMPLE: Below are TRP plots of a BT radio from CEL and a alternative solution. The plots are color coded to show strong signal (Red/Strong, Orange/Semi-strong, Yellow/Medium) and weak signal (Blue/Minimal-to-None, Green/Weak). Each plot is indexed for the respective module. Both modules are using the same transceiver chip, but the differences between them are as follows:

  • CEL...Tx Power = 0dBm, PCB Trace Antenna
  • Alternative Module...Tx Power = +8dBm, Chip Antenna

Comparing the plots show two key things…

  1. Contrasting the Tx Power Indexes on the left to one-another, CEL’s Tx signal strength is much higher, despite their Tx conducted power being significantly lower (0dBm vs. +8dBm). This shows CEL having a much more efficient antenna.

  2. CEL’s plot shows a lot of Red around the edge, which displays a strong and uniform radiation pattern (more omni directional). The Alternative Module has a lot of Blue on one side which indicates there is minimal-to-no signal, therefore, it’s more of a directional antenna.

Radiation pattern comparison between two antennas, with 'CEL' on the left showing a majority of transmit power in the upper range.

We used a range calculator and input the Rx Sensitivity, Tx Power, Gtx, Grx, and an environmental component to determine the range of each module. Additonally, we used the documented current consumption numbers at each Tx level to compare the delta between the two modules. Here are the results and summary:

Comparison table of CEL and Alternative wireless modules. CEL has 0dBm transmit power, 270m range, and 9mA current draw. Alternative has +8dBm transmit power, 201m range, and 27mA current draw. Summary states CEL has 34% greater range and 67% less power draw.

By optimizing the antenna for efficiency and omni-directional performance, CEL was able to transmit at a lower power level and still obtain better range than the alternative solution. Most importantly though, it required far less power draw to do so. CEL’s experience in working with customers to leverage superior wireless to reduce power consumption can save system cost (using smaller and cheaper cell batteries), decrease the frequency of replacing batteries, extend the charging cycle of batteries, improve thermals in the design, boost OTA performance, and enhance the end-users experience with the system or product. Please contact CEL If you would like to discuss your needs, application, and how we might help.