Wireless certification about CY8C4248LQI-BL583

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TaTa_2447651
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First solution authored 25 replies posted 10 replies posted

無線認証に関して質問です。

PSoC4(CY8C4248LQI-BL583)を使用して自社の製品開発を行っています。

日本の無線認証(工事設計認証)試験において問題が発生しているため質問させてください。

マイコンからの無線出力をアンテナの手前で直接ケーブルに接続し、2.440GHzの変調波と無変調波

を測定したところ添付のような波形が計測されました。変調波のほうは問題なさそうですが、無変調波

のほうは設定した周波数以外に隣のチャンネルの周波数も一緒に観測されており、変調が掛かっている

ような出力となっています。

製品の構成としてはCY8C4248LQI-BL583を使用しアンテナは自社開発のものとなっています。

また、試験に使用しているファームウェアは、Cypress社提供の試験用ファームを使用しています。

2点ほど質問があるのですが、

・過去にこのような現象がありましたでしょうか?あった場合、対策方法を教えて頂けますか?

・無線試験用のファームで最新のものをご提供いただけないでしょうか?

よろしくお願いいたします。

--------------------------------

This is a question about wireless certification.

We are developing a product using PSoC4 (CY8C4248LQI-BL583) and have a problem with the Japanese wireless certification test.

The wireless output from the MCU was directly connected to the cable before the antenna and a 2.440 GHz modulated wave and unmodulated waves were measured as shown in the attachment.

There seem to be no issues with the modulated signal, but the unmodulated wave has the frequency of the adjacent channel in

addition to the set frequency, and the output appears to be as if modulation is applied.

The product configuration uses CY8C4248LQI-BL583 and the antenna is developed in-house.

The firmware used for testing uses the testing firmware provided by Cypress.

1. Has this phenomenon been observed the past? If so, what countermeasures were taken?

2. Could you provide the latest wireless test firmware?

Thank you

----------------------------------

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1 Solution

Hi Takeuchi-san,

In packet transmission mode, we open the PLL loop to enable direct modulation through VCO. The initial firmware did not close the loop for carrier wave transmission. When open, the output frequency is maintained by a small capacitor, but as it discharges, the frequency would drift. The fix was to close the loop for Carrier Wave mode transmission.

By, general firmware, we guess you mean the standard BLE component. The regulatory test firmware also uses the BLE component only for test modes supported by the component. The Carrier Wave output is not supported by the component. So, you needs to use the function we have defined in the test firmware for the carrier wave output.

Thanks and regards

Ganesh

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Takashi_M
Moderator
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1000 replies posted 500 solutions authored 750 replies posted

Dear Author,

We have to apologize for late response...

Please let us confirm which test firmware you use.

It is okay to share the download link only.

thank you.

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TakashiM_61さん。

ご返信ありがとうございます。

無線認証試験で使用しているファームの開発環境を添付しました。

よろしくお願いします。

----------------------

Hi TakashiM_61.

Thank you for your reply.

The development environment of the firmware used in the wireless certification test is attached.

Best regards.

-----------------------

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Hi Takashi-san,

>>"1. Has this phenomenon been observed the past? If so, what countermeasures were taken?"

--> Yes. This was an issue in the initial versions of the firmware. This has been fixed.

>>"2. Could you provide the latest wireless test firmware?"

--> The latest firmware will be present in the KBA below. We guess you are using the old version of it. Please download the latest project from the web. The link is given below:

Test Firmware for PSoC®/PRoC™ BLE RF Certification – KBA220073

Please check and update.

Thanks

Ganesh

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Hi Ganesh-san.

Thank you for your reply.

I will check with the latest RF Certification firmware.

I have two additioanl questions.

1.

>>--> Yes. This was an issue in the initial versions of the firmware.This has been fixed.

What exactly is the initial firmware issue?

Our research has shown that the transmission has begun before the crystal locks.

Is this a same problem?

2.

Is it OK for general firmware that uses PSoC Creator to place BLE components and control using APIs?

I am worried if the same problem occurs on our device with PSoC.

The environment I am using is as follows.

PSoC Creator:4.2

BLE Component:3.61

Best regards.

--------------------------------

Ganeshさん。

ご回答ありがとうございます。

最新のRF Certificationファームウェアで確認します。

>>--> Yes. This was an issue in the initial versions of the firmware. This has been fixed.

こちらに関して質問があります。

初期バージョンのファームウェアの問題とは具体的にどういったものでしょうか?

我々が行った調査では、水晶振動子がロックする前に送信が始まっている、という結果になっています。

これと同じような問題でしょうか?あと、

もう一点確認させてください。

今回はRF Certificationファームウェアの問題ですが、通常通りPSoC CreatorでBLEコンポーネントを

配置して、APIを使用して制御するようなファームウェアの場合は同様の問題は発生しないと思って

宜しいでしょうか?

私が使用している環境は以下の通りです。

PSoC Creator:4.2

BLE Component:3.61

よろしくお願いします。

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Hi Takeuchi-san,

In packet transmission mode, we open the PLL loop to enable direct modulation through VCO. The initial firmware did not close the loop for carrier wave transmission. When open, the output frequency is maintained by a small capacitor, but as it discharges, the frequency would drift. The fix was to close the loop for Carrier Wave mode transmission.

By, general firmware, we guess you mean the standard BLE component. The regulatory test firmware also uses the BLE component only for test modes supported by the component. The Carrier Wave output is not supported by the component. So, you needs to use the function we have defined in the test firmware for the carrier wave output.

Thanks and regards

Ganesh

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Hi Ganesh-san.

I read your answer and understood it very well.

Thank you very much.

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