Frequency domain IQ. Richard Maiden - Intel

Transcription

1 Frequency domain IQ Richard Maiden - Intel

2 Compliance with IEEE Standards Policies and Procedures Subclause of the IEEE-SA Standards Board Bylaws states, "While participating in IEEE standards development activities, all participants...shall act in accordance with all applicable laws (nation-based and international), the IEEE Code of Ethics, and with IEEE Standards policies and procedures." The contributor acknowledges and accepts that this contribution is subject to The IEEE Standards copyright policy as stated in the IEEE-SA Standards Board Bylaws, section 7, and the IEEE- SA Standards Board Operations Manual, section 6.1, The IEEE Standards patent policy as stated in the IEEE-SA Standards Board Bylaws, section 6, and the IEEE-SA Standards Board Operations Manual, section 6.3, 2

3 IEEE [1914.3] [Radio over ethernet] [Jouni Korhonen Broadcomm] [tf3_1704_maiden_native_mode_1] Date: Author(s): Richard Maiden Name Affiliation Phone [optional] [optional] Richard Maiden Intel

4 Introduction For frequency domain native IQ, we need to add some more content to the document to correct and clarify. Split definition Need a description Parameters Frequency domain is block based (like containers) Need to define how subcarriers map into FFTs PRACH handling Frequency domain IQ destroys PRACH information. We need a way to transport this. 4

5 Frequency (sub-carriers) Radio frame -> CPRI (from tf3_1610_maiden_native_packet_types_2) slot slot sub-frame 7 symbols per slot Time (symbols) Radio Frame RB 12 RE/RB RE (7x1200 = 8,400 IQ values per slot) Symbol (1200 sub-carriers) 847 zeros ifft (2048) 2048 ifft example (20MHz LTE / 100MHz 5G) CP add ( )+6x( ) = 15,360 IQ values per slot tf3_1610_maiden_native_packet_types_2 5 CPRI

6 Frequency domain mode Add diagram similar to above to define split position. Frequency domain IQ is not a serial stream of data, it is similar to containers, blocks of data. Need to define how to extract these blocks. tf3_1704_maiden_native_mode_1 6/4/2017 6

7 Mapper type Currently; We define one native type We use a subtype to distinguish frequency/time What we need is; 2 nd native type for frequency domain mapper type Use number of FFT blocks for length similar to containers Keep subtype tf3_1704_maiden_native_mode_1 6/4/2017 7

8 New parameters needed We have mapper[mapperid].[contid] We need mapper[mapperid].[fftid] Name Width Default Note.scFFT Number of subcarriers per FFT.fftSize Size of i/fft.cplen Cyclic prefix length for 1 st symbol.cplenother Cyclic prefix length for other symbols tf3_1704_maiden_native_mode_1 6/4/2017 8

9 PRACH See TS for details on 3GPP Physical Channels and Modulation ads TS for Random Access Procedure. PRACH sub-carrier spacing is finer than PDSCH 1.25KHz vs 15KHz in LTE20 5G NR FFS Loss of PRACH 20MHz example - by extracting 1200sc, we loose the PRACH Need another packet type for PRACH tf3_1704_maiden_native_mode_1 6/4/2017 9

10 PRACH Example 20MHz PRACH format 0 example Uplink only (PRACH from mobile) 1. PRACH is extracted 24,576 samples Plus 3168 cyclic prefix Plus 2976 guard period Total 30,720 samples 2. PRACH aligned to baseband 3. Decimation FFT 5. //more in software tf3_1704_maiden_native_mode_1 6/4/

11 PRACH SubType Add new subtype as follows Binary Value Function b RoE Native PRACH data sub type PRACH IQ data payload with common frame header Encapsulation is exactly the same as frequency domain IQ Insert Title here 6/4/

12 PRACH Parameters We need mapper[mapperid].[fftid].[prach] Only applies in frequency domain mode. Name Width Default Note.config 6 1 PRACH configuration index.format 4 0 Defines TCP and TSEQ.PRBoffset 16 0 Physical resource block number tf3_1704_maiden_native_mode_1 6/4/

13 Motion # Add a description of the functional split consistant with tf3_1610_maiden_native_packet_types_2 Add new de/mapper type to mapper and demapper parameter list..mappertype = 3 indicates time domain native mode.mappertype = 4 indicates frequency domain native mode Add mapper[mapperid].fftid parameters as defined in page 8 of tf3_1704_maiden_native_mode_1.pdf. Editor has licence to update other areas to be consistant with the above. e.g., PCS Mover: Richard Maiden Seconder: Yes: No: Abstain: (technical motion needs >= 2/3)

14 Motion # Add new subtype for PRACH as outlined in page 11 of tf3_1704_maiden_native_mode_1.pdf. Add new parameters for PRACH as outlined in page 12 of tf3_1704_maiden_native_mode_1.pdf. Editor has licence to update other areas to be consistant with the above. e.g., PCS Mover: Richard Maiden Seconder: Yes: No: Abstain: (technical motion needs >= 2/3)