---
# System prepended metadata

title: oai

---

# oai code (C&C++)
```json=
Shift+F12//Find defined Mean
uint8_t // 8bits data 0~255
typedef //定義型態
struct //定義結構
struct mydata//定義結構mydata
{
 struct name;
 struct id;
 int math;   
}student//mydata型態變數為student
```
# Q1:LTE_DL_FRAME_PARMS Define
## Resource Block and Antennas
```json=
typedef struct LTE_DL_FRAME_PARMS
{
 uint8_t N_RB_DL&UL;//(RB 上下行 0~255)
 uint8_t eutra_band;//(OFDMA上行 SC-FDMA下行)
 uint32_t ul&ul_CarrierFreq;//(上下行載波頻率)
 uint32_t att_tx;//(TX&RX衰減)
 lte_prefix_type_t Ncp&_UL;//(0=Normal CP, 1=Extended CP)
 uint8_t nushift;//(1個RB偏移量)
 uint8_t nb_antennas_tx;//(節點的發射天線總數)
 uint8_t nb_antennas_rx;//(節點的接收天線總數)
 uint8_t nb_antenna_ports_eNB;// 
```
## FDD and TDD Confinguration
```json=
 frame_type_t frame_type;//(0 FDD, 1 TDD)
 uint8_t tdd_config;// {TDD S-subframe configuration (0-9)}
 uint8_t tdd_config_S;// srs extra symbol flag for TDD
 uint8_t srsX;// indicates if node is a UE (NODE=2) or eNB (PRIMARY_CH=0).
 uint8_t node_id;/// Indicator that 20 MHz channel uses 3/4 sampling frequency
 uint16_t dl_symbols_in_S_subframe;// Number of OFDM symbols in DL portion of S-subframe
 uint16_t ul_symbols_in_S_subframe;// Number of SC-FDMA symbols in UL portion of S-subframe
```
## Physical Channels and Signals in Radio Frame
```json=
 PRACH_CONFIG_COMMON prach_config_common;//PRACH_CONFIG
 PRACH_eMTC_CONFIG_COMMON prach_emtc_config_common;// PRACH_eMTC_CONFIG
 PUCCH_CONFIG_COMMON pucch_config_common;/// PUCCH Config Common (from 36-331 RRC spec)
 PDSCH_CONFIG_COMMON pdsch_config_common;/// PDSCH Config Common (from 36-331 RRC spec)
 PUSCH_CONFIG_COMMON pusch_config_common;/// PUSCH Config Common (from 36-331 RRC spec)
 PHICH_CONFIG_COMMON phich_config_common;/// PHICH Config (from 36-331 RRC spec)
 SOUNDINGRS_UL_CONFIG_COMMON soundingrs_ul_config_common;/// SRS Config (from 36-331 RRC spec)
 UL_POWER_CONTROL_CONFIG_COMMON ul_power_control_config_common; /// UL Power Control (from 36-331 RRC 
 spec)*mbsfn_SubframeConfig[MAX_MBSFN_AREA];
 struct NonMBSFN_SubframeConfig *non_mbsfn_SubframeConfig;// for fair RR scheduler
}LTE_DL_FRAME_PARMS;
//宣告結構LTE_DL_FRAME_PARMS型態之變數LTE_DL_FRAME_PARMS
```
# Q2:為什麼*6->N_RB_DL
## (Cell 之間間隔)
```json=

```
