RFEnOcean Device Testing: Transmitter and Receiver Measurements
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This page covers EnOcean device testing as defined in EnOcean radio protocol certification specifications. It covers various EnOcean transmitter and receiver measurements required during EnOcean conformance tests.
What is EnOcean technology?
EnOcean is an energy harvesting wireless technology designed mainly for building automation. EnOcean can also be used across industries for M2M (Machine to Machine) communication, IoT (Internet of Things), smart homes, etc.
EnOcean devices such as switches and sensors derive energy from their natural surroundings. The three major sources used by EnOcean devices include changes in temperature, variance in luminance level, and motor vibration. Hence, EnOcean does not require a battery for its operation. Moreover, it does not require wires as it is wireless in nature.
EnOcean technology uses sub-1 GHz frequency bands across the world, which include 868 MHz, 315 MHz, 902 MHz, and 928 MHz. It also uses the 2.4 GHz frequency band across the world for IoT applications.
EnOcean technology uses ASK and FSK modulation schemes in different frequency bands as defined by the standard. ASK (Amplitude Shift Keying) modulation is used by the 315 MHz and 868 MHz bands as defined in the ISO/IEC 14543-3-10 standard physical layer section. FSK (Frequency Shift Keying) modulation is used by the 902 MHz and 928 MHz frequencies.
EnOcean Certification tests
The following tests are defined in the EnOcean certification specification as per the ASK modulation air interface. The EnOcean certification tests require the following EnOcean test equipment. The conformance or certification tests help in assuring whether EnOcean devices operate as desired or not as per EnOcean protocol specifications.
- Signal generator: It is used to test the receiver part of the EnOcean DUT (Device Under Test).
- Signal analyzer: It is used to test the transmitter part of the EnOcean DUT (Device Under Test).
- Climate chamber: To maintain required environmental conditions as per test requirements.
- Automated test system (ATS): This system helps in certain tests where automatic trigger transmission and reception at certain time instants are needed. It is used to acquire logs during long duration tests.
EnOcean transmitter tests
In this test, the DUT (Device Under Test) is connected with a signal analyzer having specific measurement accuracy. The signal analyzer validates the DUT transmitter part by measuring, decoding, and analyzing the physical layer, data link layer, and network layer.
The following table mentions EnOcean tests for the transmitter part.
| Transmitter tests | Description with Pass criteria |
|---|---|
| Frequency Error | It should not exceed +/- 82.634 KHz (maximum). |
| Output power | It should not exceed +13 dBm (Under all test conditions). Deviation of +/- 3 dB relative to output power of DUT as mentioned by manufacturer in the datasheet. |
| Output power stability | It should not exceed +2 dB (positive maximum) and -1 dB (negative maximum). |
| Modulation | It should test both ASK and FSK modulated frames. The signal analyzer demodulates and decodes the frames with different modulation parameters set in the DUT. |
| Duty Cycle | This test is carried out as per national regulations to check how much time the DUT is transmitting the frame. |
| Encoding of frame | This test ensures whether encoding of subtelegram to frame is as per defined format or not. |
EnOcean receiver tests
In this test, the DUT (Device Under Test) is connected with a signal generator capable of generating EnOcean standard compliant signals.
The signal generator transmits a signal using different RF parameters such as frequency, power, and modulation as per test case requirement. The signal generator uses telegram and subtelegram with data and timing as specified in the ISO document to validate the data link layer and network layer respectively.
The following table mentions EnOcean tests for the receiver part.
| Receiver tests | Description with Pass criteria |
|---|---|
| Modulation test | Different modulation test scenarios are mentioned in the certification document. |
| Center frequency test | It is done to test whether the receiver performs demodulation as desired at the center frequency. |
| Sensitivity | -95 dBm or less with conditions as defined in the standard |
| Maximum Power level | -23 dBm or more |
| Blocking | The test checks whether the receiver rejects all the undesired frequencies adjacent to the operating frequency. |
| Demodulation robustness | Subtelegram error rate should not exceed 12.9% under test conditions defined. |
| Decoding of frame | This test ensures whether the DUT decodes all the frames without error or not. It also checks whether the DUT discards all incorrect frames or not. |
The common EnOcean tests include the following.
- Tx-Rx Switch Over Time: It checks the time required for the EnOcean transceiver to switch from the transmitting state to the receiving state. This is defined in the manufacturer datasheet.
Refer to the EnOcean Certification Specification for test setup and measurement procedure. Frame patterns for different test cases with subtelegram and telegram details are defined in the certification document.
References
- EnOcean Certification Specification (part 1a), Air Interface (ASK) V1.4, Released on Feb.10, 2019
- Visit www.enocean.com for everything you would like to know about EnOcean technology from the inventor and pioneer of this energy harvesting wireless technology.
- EnOcean Alliance
