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From:   Kalle Valo <kvalo@codeaurora.org>
To:     Tony Chuang <yhchuang@realtek.com>
Cc:     "linux-wireless\@vger.kernel.org" <linux-wireless@vger.kernel.org>,
        "briannorris\@chromium.org" <briannorris@chromium.org>,
        "sgruszka\@redhat.com" <sgruszka@redhat.com>
Subject: Re: [PATCH 4/8] rtw88: 8822c: add FW IQK support
References: <1565174405-2689-5-git-send-email-yhchuang@realtek.com>
        <20190903125324.4CDC76085C@smtp.codeaurora.org>
        <F7CD281DE3E379468C6D07993EA72F84D18C6B3B@RTITMBSVM04.realtek.com.tw>
Date:   Fri, 06 Sep 2019 17:13:42 +0300
In-Reply-To: <F7CD281DE3E379468C6D07993EA72F84D18C6B3B@RTITMBSVM04.realtek.com.tw>
        (Tony Chuang's message of "Wed, 4 Sep 2019 02:31:42 +0000")
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Tony Chuang <yhchuang@realtek.com> writes:

>> 
>> <yhchuang@realtek.com> wrote:
>> 
>> > From: Yan-Hsuan Chuang <yhchuang@realtek.com>
>> >
>> > Add support for doing IQK in firmware
>> >
>> > Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
>> 
>> The commit log does not answer "Why?". What is IQK and how does it help?
>> 
>> No need to resend, I can update the commit log but just let me know what to
>> add.
>> 
>
> Ideally the RF component's I/Q vectors should be orthogonal, but usually they are not.
> So we need to calibrate for the RF components, ex. PA/LNA, ADC/DAC.
>
> And if the I/Q vectors are more orthogonal, the mixed signal will have less deviation.
> This helps with those rates with higher modulation (MCS8-9), because they have more
> strict EVM/SNR requirement. Also the better of the quality of the signal, the longer it
> can propagate, and the better throughput performance we can get.

I added this to patch 4 but there were some warnings so I had drop the
patches. So please send v2 and remember to add this description to patch
4.

-- 
Kalle Valo