Re: [Discuss-gnuradio] Wideband OFDM Reference Implementation

[Michael Dickens]

Hi Yaşar - To address your first paragraph / question: the GR OFDM has not been updated significantly since that post. It can still handle FFT length of 64: yes! It might be able to handle 128 or higher, or 32 or lower, out of the box. The error you provide shows that it is not able to handle the larger incoming PDUs for length 128. An option you have is to set (e.g., in GRC) the "Min Output Buffer" to a larger value, say 100000 (bytes), for the GR OFDM hierarchal blocks. This value will be propagated through to the (actual) blocks that make it up and, with a high enough value, should fix the immediate issue. Hope this is useful. - MLD

On Tue, Mar 13, 2018, at 6:43 PM, Yaşar Sinan Nasır wrote:

Yes, after some trial with the provided OFDM .grc files of the GNU Radio, I agree with you on the flexibility of the occupied bins and pilot tones. However, I have an issue. When, I try FFT length input that is greater than 64, I get "<block ofdm_carrier_allocator_cvc (14)>]: Buffer too small for min_noutput_items" error. After a search in the forum I found your comment in https://lists.gnu.org/archive/html/discuss-gnuradio/2014-08/msg00223.html Could you please give more details on what needs to be changed. e.g., do we have to change the source code of the OFDM Carrier Allocator block?