為什麼這篇mixer原理鄉民發文收入到精華區：因為在mixer原理這個討論話題中，有許多相關的文章在討論，這篇最有參考價值！作者poppyya (yeh)看板comm_and_RF標題[請益]時間Wed Sep 9 12:...
請教一下各位~
因為小妹之前沒接觸過MIXER
現在想做一個MIXER跟LNA的電路整合
但無從下手 PAPER 裡有提到 LO IF...等等
想請教一下這些是啥??
還是說哪邊可以查到MIXER的原理
拜託高手了!!
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◆ From: 140.134.30.130
※ 編輯: poppyya 來自: 140.134.30.130 (09/09 12:50)
推 youwin0125:關鍵字出現了 "小妹" 60.250.209.199 09/09 16:09
推 deathcustom:youwin你真糟糕= = 122.116.95.114 09/09 19:18
→ pow:Y大搶了D大表現的機會 好糟糕 74.242.226.152 09/09 20:12
推 youwin0125:完蛋了 會被D大 打 >< 114.43.201.63 09/09 20:26
→ poppyya:真得是非常謝謝各位!!!! 114.46.144.226 09/10 00:29
推 wrltertina:幹嗎學人家 113.52.127.251 09/19 01:58
> -------------------------------------------------------------------------- <
作者: Lary (PTTuser) 看板: comm_and_RF
標題: Re: [請益] RF MIXER
時間: Wed Sep 9 23:43:22 2009
※ 引述《poppyya (yeh)》之銘言：
: 請教一下各位~
: 因為小妹之前沒接觸過MIXER
: 現在想做一個MIXER跟LNA的電路整合
: 但無從下手 PAPER 裡有提到 LO IF...等等
: 想請教一下這些是啥??
: 還是說哪邊可以查到MIXER的原理
: 拜託高手了!!
我覺得如果你對RF完全外行
你可以看一下Razavi的書瞭解一下RF system的架構
detail的mixer電路如果是CMOS製程的話
我個人推薦Thomas Lee的書
至於你要做的mixer要看你是用在怎樣的system
若是protable的話可能要找passve mixer
若是不考慮耗電的話可以找active mixer
differential signal
不需要產生IQ的話可以用Giber cell
若是要產生IQ的話可能要用double balance的結構
single signal的話只要一顆device
detail可能就要自己看書囉
我也不是很熟
一點點自己的看法
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◆ From: 123.195.2.141
推 poppyya:嗯嗯...謝謝你! 不過被動的MIXER也可以做 114.46.144.226 09/10 00:31
→ poppyya:在TSMC 0.18um裡嗎?? 114.46.144.226 09/10 00:31
推 louisyan:可以 114.32.224.66 09/10 05:43
推 carrack:of course for .18 process 72.130.190.120 09/10 10:53
→ carrack:your MOSFETs just simply act as switch 72.130.190.120 09/10 10:54
→ carrack:but not sure with passive for low power 72.130.190.120 09/10 10:56
→ carrack:usually passive mixer need larger LO 72.130.190.120 09/10 10:57
→ carrack:larger LO driver can kill you in power 72.130.190.120 09/10 10:58
→ carrack:also linearity could be a concern 72.130.190.120 09/10 10:59
→ carrack:if really want to do passive in 0.18um 72.130.190.120 09/10 11:00
→ carrack:ask DNW option from your Boss 72.130.190.120 09/10 11:01
→ carrack:however, i am not expert of mixer 72.130.190.120 09/10 11:03
→ carrack:all above is only my suspicion 72.130.190.120 09/10 11:03
→ Lary:可以的 基本上也是用rfmos只是沒有流電流 123.195.2.141 09/10 17:45
→ Lary:但是你要設計好gate電壓 令LO swing可以對mos 123.195.2.141 09/10 17:46
→ Lary:造成switch的效果 device size也要選一下 123.195.2.141 09/10 17:46
→ Lary:會影響妳LO在你輸入的頻旅看到的阻抗 123.195.2.141 09/10 17:47
→ Lary:好像說錯了 不是gate電壓 是S/D電壓 123.195.2.141 09/10 17:49
推 poppyya:嗯~ 謝謝各位^^ 114.46.113.58 09/11 00:27
→ poppyya:再問一下喔~ IF 中頻 要去哪裡查? 114.46.113.58 09/11 00:31
→ poppyya:我的意思是 如果我做2.4GHz的MIXER 那IF? 114.46.113.58 09/11 00:31
→ poppyya:這要到哪裡才查的到??? 謝謝了!! 114.46.113.58 09/11 00:32
→ Lary:也許你應該先說妳到底要做什麼樣的系統? 123.195.2.141 09/11 00:38
→ Lary:不同調變方式需要不同的頻寬 這可能需要做 123.195.2.141 09/11 00:39
→ Lary:system或baseband的人來訂到底if的center 123.195.2.141 09/11 00:40
→ Lary:freq. 和band width是多少 然後決定DAC到 123.195.2.141 09/11 00:41
→ Lary:mixer間的LPF design 123.195.2.141 09/11 00:41
推 Gocoba:不同的架構有不同的IF 同時也牽扯到Image 72.222.132.58 09/11 01:12
→ Gocoba:rejection的問題 還有filter的設計 72.222.132.58 09/11 01:12
→ Lary:image rejection感覺跟poly-phase filter140.113.228.149 09/11 17:29
→ Lary:以及LO的I-Q error比較有關係ㄟ...140.113.228.149 09/11 17:30
推 carrack:Lary, you are talking about zero-IF sys 63.239.159.137 09/11 23:44
→ Lary:I am talking about low IF system 60.250.197.166 09/12 11:53
→ Lary:I'm not sure if the mixer design is differ 60.250.197.166 09/12 12:02
→ Lary:ent for zero-IF and low-IF. However, the 60.250.197.166 09/12 12:02
→ Lary:difficult part of zero-IF design would be 60.250.197.166 09/12 12:03
→ Lary:how to remove DC offset due to device mism 60.250.197.166 09/12 12:04
→ Lary:atch or other factors without affecting th 60.250.197.166 09/12 12:04
→ Lary:e wanted signal. A HPF with very low 3dB 60.250.197.166 09/12 12:05
→ Lary:freq will need a large layout area and lon 60.250.197.166 09/12 12:06
→ Lary:g stable time. I did not do it myself. 60.250.197.166 09/12 12:07
→ Lary:I do not know it very well and we can 60.250.197.166 09/12 12:09
→ Lary:discuss if you are interested. 60.250.197.166 09/12 12:09
> -------------------------------------------------------------------------- <
作者: carrack (.....) 看板: comm_and_RF
標題: Re: [請益] RF MIXER
時間: Sun Sep 13 23:38:59 2009
Hey Lary thanks for your opinion!
Sorry I am not in Taiwan and need to use English typing sys.
Yes, I agree with you zero-IF has some DC issue compared with low-IF.
However, we are not necessary to use "physical" HPF to deal with that in
the industry.
Why I said maybe you are talking about zero-IF system is because of the
image rejection issue.
Because the image of zero/low-IF system is usually located in your own
application band, it is impossible to design a image rejection filter to
kill them. That's why we need image cancellation Mixer/sys.
Sure, as you said the mismatch of IQ path will degrade the image rejection,
if we don't do any correction I think maybe only ~ -40dB we can get in current
technology.
In heterodyne system, it is a different story. If we can choose the IF cleverly
then the image can be located some less interference band and we don't need
high rejection level.
Also, the IF selection will affect the channel filter and image(band) filter
design. In most cases, they are directly trade-off.
Anyway, really appreciate your idea and I agree with you direction conversion
type sys is the main-stream now and maybe IQ mismatch has more effect on the
image issue.
※ 引述《Lary (PTTuser)》之銘言：
: 推 poppyya:嗯~ 謝謝各位^^ 114.46.113.58 09/11 00:27 : → poppyya:再問一下喔~ IF 中頻 要去哪裡查? 114.46.113.58 09/11 00:31 : → poppyya:我的意思是 如果我做2.4GHz的MIXER 那IF? 114.46.113.58 09/11 00:31 : → poppyya:這要到哪裡才查的到??? 謝謝了!! 114.46.113.58 09/11 00:32 : → Lary:也許你應該先說妳到底要做什麼樣的系統? 123.195.2.141 09/11 00:38 : → Lary:不同調變方式需要不同的頻寬 這可能需要做 123.195.2.141 09/11 00:39 : → Lary:system或baseband的人來訂到底if的center 123.195.2.141 09/11 00:40 : → Lary:freq. 和band width是多少 然後決定DAC到 123.195.2.141 09/11 00:41 : → Lary:mixer間的LPF design 123.195.2.141 09/11 00:41 : 推 Gocoba:不同的架構有不同的IF 同時也牽扯到Image 72.222.132.58 09/11 01:12 : → Gocoba:rejection的問題 還有filter的設計 72.222.132.58 09/11 01:12 : → Lary:image rejection感覺跟poly-phase filter 140.113.228.149 09/11 17:29 : → Lary:以及LO的I-Q error比較有關係ㄟ... 140.113.228.149 09/11 17:30 : 推 carrack:Lary, you are talking about zero-IF sys 63.239.159.137 09/11 23:44 : → Lary:I am talking about low IF system 60.250.197.166 09/12 11:53 : → Lary:I'm not sure if the mixer design is differ 60.250.197.166 09/12 12:02 : → Lary:ent for zero-IF and low-IF. However, the 60.250.197.166 09/12 12:02 : → Lary:difficult part of zero-IF design would be 60.250.197.166 09/12 12:03 : → Lary:how to remove DC offset due to device mism 60.250.197.166 09/12 12:04 : → Lary:atch or other factors without affecting th 60.250.197.166 09/12 12:04 : → Lary:e wanted signal. A HPF with very low 3dB 60.250.197.166 09/12 12:05 : → Lary:freq will need a large layout area and lon 60.250.197.166 09/12 12:06 : → Lary:g stable time. I did not do it myself. 60.250.197.166 09/12 12:07 : → Lary:I do not know it very well and we can 60.250.197.166 09/12 12:09 : → Lary:discuss if you are interested. 60.250.197.166 09/12 12:09
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 66.27.100.30
> -------------------------------------------------------------------------- <
作者: Lary (PTTuser) 看板: comm_and_RF
標題: Re: [請益] RF MIXER
時間: Mon Sep 14 20:48:13 2009
Hi Carrack
Thank you for your valuable opinion.
Since I am just a freshman in RF field, I am not familiar with HPF in baseband
and image rejection correction in baseband.
I am very intersted in both of them, especially the correction for image
rejection (Did they control the IQ phase by baseband?)x.
Can you kindly provid some relative paper, patent, or books for me?
Recently I also face some problems of adjacent channel rejection ration due to
insufficient image rejection ratio.
In our case, the poly-phase filter can only provid 30 dB image rejection.
I am wondering how can we improve it in baseband.
Thank you for your reply.
※ 引述《carrack (.....)》之銘言：
: Hey Lary thanks for your opinion!
: Sorry I am not in Taiwan and need to use English typing sys.
: Yes, I agree with you zero-IF has some DC issue compared with low-IF.
: However, we are not necessary to use "physical" HPF to deal with that in
: the industry.
: Why I said maybe you are talking about zero-IF system is because of the
: image rejection issue.
: Because the image of zero/low-IF system is usually located in your own
: application band, it is impossible to design a image rejection filter to
: kill them. That's why we need image cancellation Mixer/sys.
: Sure, as you said the mismatch of IQ path will degrade the image rejection,
: if we don't do any correction I think maybe only ~ -40dB we can get in current
: technology.
: In heterodyne system, it is a different story. If we can choose the IF cleverly
: then the image can be located some less interference band and we don't need
: high rejection level.
: Also, the IF selection will affect the channel filter and image(band) filter
: design. In most cases, they are directly trade-off.
: Anyway, really appreciate your idea and I agree with you direction conversion
: type sys is the main-stream now and maybe IQ mismatch has more effect on the
: image issue.
: ※ 引述《Lary (PTTuser)》之銘言：
: : 推 poppyya:嗯~ 謝謝各位^^ 114.46.113.58 09/11 00:27 : : → poppyya:再問一下喔~ IF 中頻 要去哪裡查? 114.46.113.58 09/11 00:31 : : → poppyya:我的意思是 如果我做2.4GHz的MIXER 那IF? 114.46.113.58 09/11 00:31 : : → poppyya:這要到哪裡才查的到??? 謝謝了!! 114.46.113.58 09/11 00:32 : : → Lary:也許你應該先說妳到底要做什麼樣的系統? 123.195.2.141 09/11 00:38 : : → Lary:不同調變方式需要不同的頻寬 這可能需要做 123.195.2.141 09/11 00:39 : : → Lary:system或baseband的人來訂到底if的center 123.195.2.141 09/11 00:40 : : → Lary:freq. 和band width是多少 然後決定DAC到 123.195.2.141 09/11 00:41 : : → Lary:mixer間的LPF design 123.195.2.141 09/11 00:41 : : 推 Gocoba:不同的架構有不同的IF 同時也牽扯到Image 72.222.132.58 09/11 01:12 : : → Gocoba:rejection的問題 還有filter的設計 72.222.132.58 09/11 01:12 : : → Lary:image rejection感覺跟poly-phase filter 140.113.228.149 09/11 17:29 : : → Lary:以及LO的I-Q error比較有關係ㄟ... 140.113.228.149 09/11 17:30 : : 推 carrack:Lary, you are talking about zero-IF sys 63.239.159.137 09/11 23:44 : : → Lary:I am talking about low IF system 60.250.197.166 09/12 11:53 : : → Lary:I'm not sure if the mixer design is differ 60.250.197.166 09/12 12:02 : : → Lary:ent for zero-IF and low-IF. However, the 60.250.197.166 09/12 12:02 : : → Lary:difficult part of zero-IF design would be 60.250.197.166 09/12 12:03 : : → Lary:how to remove DC offset due to device mism 60.250.197.166 09/12 12:04 : : → Lary:atch or other factors without affecting th 60.250.197.166 09/12 12:04 : : → Lary:e wanted signal. A HPF with very low 3dB 60.250.197.166 09/12 12:05 : : → Lary:freq will need a large layout area and lon 60.250.197.166 09/12 12:06 : : → Lary:g stable time. I did not do it myself. 60.250.197.166 09/12 12:07 : : → Lary:I do not know it very well and we can 60.250.197.166 09/12 12:09 : : → Lary:discuss if you are interested. 60.250.197.166 09/12 12:09
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◆ From: 123.195.37.160