'하드웨어/lora lorawan' 카테고리의 글 목록

'하드웨어/lora lorawan'에 해당되는 글 3건

2025.12.16 LoRa modulation basics
2025.12.16 lora CR(coding rate)
2025.10.02 lora evk

lora CR(coding rate) (0)	2025.12.16
lora evk (0)	2025.10.02

lora CR(coding rate)

래핑 모듈만 사용하다 보니, SF / 주파수만 신경썼었는데

sx1276 데이터 시트를 보다보니 CR(Coding Rate)라는게 있어서 먼지 감이 안와서(메뉴얼 상에서는) 찾아보니

FEC를 위한 추가 비트를 이야기 하고, 순수데이터/패리티포함데이터 길이로 보면 된다고 한다.

4/5는 4bit data + 1bit parity

4/6은 4bit data + 2bit parity

4/7은 4bit data + 3bit parity

4/8은 4bit data + 4bit parity 식인셈

4.1.1.3. Coding Rate
To further improve the robustness of the link the LoRa® modem employs cyclic error coding to perform forward error
detection and correction. Such error coding incurs a transmission overhead - the resultant additional data overhead per
transmission is shown in the table below.

Forward error correction is particularly efficient in improving the reliability of the link in the presence of interference. So that
the coding rate (and so robustness to interference) can be changed in response to channel conditions - the coding rate can
optionally be included in the packet header for use by the receiver. Please consult Section 4.1.1.6 for more information on
the LoRa® packet and header.

[링크 : https://blog.naver.com/bae3421_/221274850012]

FEC - Forward Error Correction

[링크 : http://www.ktword.co.kr/test/view/view.php?no=693]

CRC -Cyclic Redundancy Checking

[링크 : http://www.ktword.co.kr/test/view/view.php?nav=2&no=603&sh=crc]

FEC는 전송할때 복구를 위한 데이터를 포함하여 전송하여 correction에 포인트를 두는 전송방식이고

CRC는 정정이 아니라 에러가 있음을 확인하는 방법이다.

저작자표시 (새창열림)

'하드웨어 > lora lorawan' 카테고리의 다른 글

LoRa modulation basics (0)	2025.12.16
lora evk (0)	2025.10.02

Posted by 구차니

lora evk

중앙의 뚜껑있는 놈이 stm32L 과 sx1276 통합 모듈, 왼쪽은 stlink 인듯.

The B-L072Z-LRWAN1 LoRa®/Sigfox™ Discovery kit is a development tool to learn and develop solutions based on LoRa®, Sigfox™, and FSK/OOK technologies. This Discovery kit features the all-in-one CMWX1ZZABZ-091 open module by Murata. The module is powered by an STM32L072CZ microcontroller and SX1276 transceiver. The transceiver features the LoRa® long-range modem, providing ultra-long-range spread-spectrum communication and high interference immunity, minimizing current consumption. Since CMWX1ZZABZ-091 is an open module, the user has access to all STM32L072CZ peripherals such as ADC, 16-bit timer, LP-UART, I2C, SPI, and USB 2.0 FS (supporting BCD and LPM).

[링크 : https://www.st.com/en/evaluation-tools/b-l072z-lrwan1.html]

[링크 : https://www.murata.com/en-global/products/connectivitymodule/lpwa/overview/lineup/type-abz-091]

FSK (Frequency Shift Keying)
OOK (On-Off Keying)

[링크 : https://blog.naver.com/bruno_annie/220777474513]

[258199.737417] usb 1-2: new full-speed USB device number 31 using xhci_hcd
[258199.866439] usb 1-2: New USB device found, idVendor=0483, idProduct=374b, bcdDevice= 1.00
[258199.866457] usb 1-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[258199.866464] usb 1-2: Product: STM32 STLink
[258199.866470] usb 1-2: Manufacturer: STMicroelectronics
[258199.866475] usb 1-2: SerialNumber: 066BFF363637503457160939
[258199.927997] usb-storage 1-2:1.1: USB Mass Storage device detected
[258199.928972] scsi host0: usb-storage 1-2:1.1
[258199.930589] cdc_acm 1-2:1.2: ttyACM0: USB ACM device
[258200.938237] scsi 0:0:0:0: Direct-Access MBED microcontroller 1.0 PQ: 0 ANSI: 2
[258200.939003] sd 0:0:0:0: Attached scsi generic sg0 type 0
[258200.940836] sd 0:0:0:0: [sda] 456 512-byte logical blocks: (233 kB/228 KiB)
[258200.941073] sd 0:0:0:0: [sda] Write Protect is off
[258200.941080] sd 0:0:0:0: [sda] Mode Sense: 03 00 00 00
[258200.941299] sd 0:0:0:0: [sda] No Caching mode page found
[258200.941312] sd 0:0:0:0: [sda] Assuming drive cache: write through
[258200.963802] sd 0:0:0:0: [sda] Attached SCSI removable disk

[링크 : https://os.mbed.com/platforms/ST-Discovery-LRWAN1/]

[링크 : https://os.mbed.com/teams/ST/code/DISCO-L072CZ-LRWAN1_LoRa_PingPong/]