Looking for RF to I/Q Integrated Solution

- What is the use case? Eq why do you want the raw IQ data?
- With CC1120 you could also do this, check table 10 in the UserGuide.

Thanks for your quick response.

- I am building a custom baseband solution and hence need access to raw i/q data.
- We have been working with CC1101 for a few months now (part of CC430 solution) and it would be great if we can have access to I/Q data. We have done quite a bit of experiments on CC1101 manual and I can't seem to find any mention of access to raw I/Q data. The CC1101 manual does say we have access to 'raw data' in asynchronous mode where no 'data-decisions' are made but I can't seem to find what exactly this raw data is. Is it after the demodulator? Is it after the channel filter? Is it right after the ADC in the receive path?
- I would like more information about the oversampling of 8 times in the asynchronous mode. Why do Tx/Rx oversample the data 8*times?
- I did see a mention of access to ADC data in CC1120. But the manual says it is 'test-only'. If we were to switch to CC1120 solution now, we would like to know if this I/Q ADC data can be relied up on to do custom baseband processing in production solution instead of the 'test-only' mode that the manual says? What is impact on the radio (and eventually on I/Q samples) in test-mode?

Thanks,
Vipin

Thanks.
We may be able tolerate 10-20dB of degradation.

I am still very curious as to what 'raw data' means for CC1101; the manual does not have enough information about this. "The CC1101 manual does say we have access to 'raw data' in asynchronous mode where no 'data-decisions' are made but I can't seem to find what exactly this raw data is. Is it after the demodulator? Is it after the channel filter? Is it right after the ADC in the receive path?"

Thanks,
Vipin

Thanks for the information. This is exactly what I was looking for.

Our team will be able to save quite a bit of time if we can get this done on CC1101 itself. Is there any way I can get more information on how to access the I/Q data if GDO_CFGx is programmed to 0x10? How do I select I vs Q on teh GDO output?

This is clearly documented in CC1120 dataset. Should I assume the same setting for CC1101 as well?

I checked with the designer involved in the IQ output on CC1101. I thought the same as Thomas, that the performance got reduced 10 -20 dB by doing it this way but it turn out that the noise from the pad toggling will cause the ADC to be unstable. Hence CC1101 based radios are not a real option for raw IQ signals.

Thanks for your response. 

In that case we will not go for CC1101 for our prototype/production solution. 

Are there any other low cost solutions from TI which do allow production quality access to I/Q data? We don't have RF expertise in the team and would ideally like all RF front end integrated on the chip and just provide access to I/Q data in the lower ISM band range (0-1Ghz) with bandwidth close to 50Mhz. 

Our cost limitations for this chip is around $10/part.

Thanks,

Vipin

Vipin, 

In the Low Power wireless group we do not have anything that does 50MHz bandwidth. In the High speed group there are parts that will do this and I was involved in designing a RF front end using this components that I would recommend that you take a look at.

This solution will give you carrier grade performance with up to 60MHz IF bandwidth for options to go to even higher.

Regards,
/TA

Vipin,

what sort of radio do you need 50 MHz bandwidth for?

Our application requires spectrum analysis over a wide domain of frequency ranges.

I can search myself on Ti's website for different solutions if I know what to look for. For example I have tried 'integrated quardrature receiver', Rf to I/q, baseband receiver, and several other nomenclatures but could not find any. I also tried doing parametric search but that didn't go anywhere because I didn't know how to specify I/q outputs as one of the requirements.

We would really like to stick to TI's solution simply because of excellent support here and also because of existing familiarity we have in the team.

Thanks,
Vipin

Do you actually look at 50 MHz at a time? Sweeping is not an option?

What is the expected volume for this product?

In this forum we are covering wireless connectivity and don't have the full overview the full TI portfolio.

We don't necessarily need 50MHz at a time. Sweeping is an option. In this scenario, what TI products would suit us?

Our product is in early prototyping stage and we estimate our first shipments to be in the order of a few thousands.

Thanks,

Vipin