Bluetooth EDR RF Test (Part 3)

    At present, the speed of updating and replacing of various communication products is very fast. The quality and function of products are the foundation for the survival of products. For a product put on the market, it must not only have the corresponding functions, but more importantly, all parameters and indicators of the product must meet the requirements of specifications and standards. How to effectively ensure the quality of products is a crucial issue in the design and production process. For example, in the design and production process of Bluetooth products, RF testing is an important step to ensure the quality of Bluetooth products. In order to facilitate testing and increase the speed of product updates, Moore Lab provides you with a complete set of testing solutions. The following is some introduction to Bluetooth EDR RF testing:

    Currently, the Bluetooth EDR test mainly adopts the BLUETOOTH SPECIFICATION Version 2.1 + EDR standard. The tests defined in this standard are divided into transmitter test (TRM) and receiver test (TRV). This article introduces one of the transmitter tests.

    EDR test item EDR Carrier Frequency Stability and Modulation Accuracy
    Test Intent: This test needs to identify the stability and accuracy of the carrier frequency of the transmitter of the device under test.

    Test method:
    1. Connect the EUT to the test system through a 50Ω connector or a 50Ω external antenna.
    2. Enter the EUT test mode, set the test system to loopback mode and turn off the Whitening function.
    3. Turn off hopping when the system enters the test environment.
    4. The EUT transmits a very low signal.
    5. The EUT under test transmits a minimum signal.
    6. The EUT under test will be connected to the test instrument with the maximum power output. (For the specific system test process, refer to 5.1.13 in the standard RF.TS.2.1.E.1)
    7. Set the center frequency of the EUT to start the test, and use the deviation of the center frequency to identify the stability and accuracy of the carrier frequency of the transmitter of the EUT.

    Test results: All test values ​​must meet the following conditions.

    1. Carrier frequency stability:
    -75 kHz < ωi < +75 kHz, for all packets
    -75 kHz < (ωi + ω0) < +75 kHz, for all blocks
    -10 kHz <ω0 < +10 kHz, for all blocks

    2. RMS DEVM:
    RMS DEVM < 0.20, for all π/4-DQPSK blocks
    RMS DEVM < 0.13, for all 8DPSK blocks

    3. Peak DEVM:
    DEVM < 0.35 for all π/4-DQPSK symbols
    DEVM < 0.25 for all 8DPSK symbols

    4. 99% DEVM:
    DEVM < 0.30, for 99% of π/4-DQPSK symbols
    DEVM < 0.20, for 99% of 8DPSK symbols

    The above is a brief introduction to some Bluetooth EDR transmitter test items. If you want to know more details, please contact MORLAB.