Direct conversion becomes a common practice for CMOS radio

Status
Not open for further replies.

iamlog

Newbie level 5
Joined
Mar 26, 2004
Messages
9
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
97
Recently search the literature, found that now Zero-IF has became the common practice for CMOS radio implementation. Two years ago I was thinking that direct conversion is impossible....technology advance is really amazing!

Any other architecture seems promising? how about sub-sampling?
 

Re: Direct conversion becomes a common practice for CMOS rad

research is into sub sampling right now...

i know people doing it for their PhD's...

the trend -- less analog and more digital.

used signal processing to do everything, keep analog minimal.

sampling everywhere... TI is already doing it.
 

Re: Direct conversion becomes a common practice for CMOS rad

Wide bandwidth and spread-spectrum technique make it possible to employ direct downconversion receivers. The negative effect of DC offset and flicker noise is reduced to a negligiable level.

IEEE802.11a is very suitalbe for dir-con architecture to make a highly integrated, low power and low cost chipset.
 

Re: Direct conversion becomes a common practice for CMOS rad

But at this time, it looks that the only CMOS 802.11a product is from Atheros, who actually did not use the direct-conversion. Other comapnies, such as Broadcom, RFMD, Athena Semi, have publications using direct-conversion, but not a product. I guest direct-conversion still is a challenging task...
 

Re: Direct conversion becomes a common practice for CMOS rad

Two years ago I was thinking that direct conversion is impossible.

Nokia phones have used direct conversion on TX and RX for
about 5 years now. However the RFICs in this case are BiCMOS.
Others, such as Siemens with their Smarti DC chips do the same..
 

Status
Not open for further replies.
Cookies are required to use this site. You must accept them to continue using the site. Learn more…