英国CanSat竞赛LoRa接收消息出现乱码符号的解决求助

我正在参加英国CanSat竞赛，当前调试CanSat与地面站的LoRa通信：

• 发射端：Raspberry Pi Pico
• 接收端：Arduino Nano
• LoRa模块：Adafruit RFM95W

目前遇到的核心问题：地面站接收消息时出现大量乱码，截图如下：

Arduino接收端代码 #

// Arduino9x_RX
// -*- mode: C++ -*-
// Example sketch showing how to create a simple messaging client (receiver)
// with the RH_RF95 class. RH_RF95 class does not provide for addressing or
// reliability, so you should only use RH_RF95 if you do not need the higher
// level messaging abilities.
// It is designed to work with the other example Arduino9x_TX

#include <SPI.h>
#include <RH_RF95.h>

#define RFM95_CS 10
#define RFM95_RST 9
#define RFM95_INT 2

// Change to .0 or other frequency, must match RX's freq!
#define RF95_FREQ 433.0

// Singleton instance of the radio driver
RH_RF95 rf95(RFM95_CS, RFM95_INT);

// Blinky on receipt
#define LED 13

void setup() {
  pinMode(LED, OUTPUT);     
  pinMode(RFM95_RST, OUTPUT);
  digitalWrite(RFM95_RST, HIGH);

  while (!Serial);
  Serial.begin(9600);
  delay(100);

  Serial.println("Arduino LoRa RX Test!");
  
  // manual reset
  digitalWrite(RFM95_RST, LOW);
  delay(10);
  digitalWrite(RFM95_RST, HIGH);
  delay(10);

  while (!rf95.init()) {
    Serial.println("LoRa radio init failed");
    while (1);
  }
  Serial.println("LoRa radio init OK!");

  // Defaults after init are 434.0MHz, modulation GFSK_Rb250Fd250, +13dbM
  if (!rf95.setFrequency(RF95_FREQ)) {
    Serial.println("setFrequency failed");
    while (1);
  }
  Serial.print("Set Freq to: "); Serial.println(RF95_FREQ);

  // Defaults after init are 434.0MHz, 13dBm, Bw = 125 kHz, Cr = 4/5, Sf = 128chips/symbol, CRC on

  // The default transmitter power is 13dBm, using PA_BOOST.
  // If you are using RFM95/96/97/98 modules which uses the PA_BOOST transmitter pin, then 
  // you can set transmitter powers from 5 to 23 dBm:
  rf95.setTxPower(23, false);
}

void loop() {
  if (rf95.available()) {
    // Should be a message for us now   
    uint8_t buf[RH_RF95_MAX_MESSAGE_LEN];
    //char buf = (char*)buf;
    uint8_t len = sizeof(buf);
    
    if (rf95.recv(buf, &len)) {
      digitalWrite(LED, HIGH);
      Serial.print("Got: ");
      Serial.println((char*)buf);
      Serial.print("RSSI: ");
      Serial.println(rf95.lastRssi(), DEC);
    } else {
      return;
    }
  }
}

注：代码来自Arduino社区论坛示例。

Raspberry Pi Pico发射端代码 #

import board
import busio
import time
import digitalio
import adafruit_rfm9x
import adafruit_bmp280

"Led configuration"
# Led amarillo
ledambar = digitalio.DigitalInOut(board.GP16)
ledambar.direction = digitalio.Direction.OUTPUT

# Led azul
ledazul = digitalio.DigitalInOut(board.GP17)
ledazul.direction = digitalio.Direction.OUTPUT

"LoRa"
# LoRa radio setup

spi = busio.SPI(clock=board.GP2, MOSI=board.GP3, MISO=board.GP4)
cs = digitalio.DigitalInOut(board.GP6)
reset = digitalio.DigitalInOut(board.GP7)
rfm9x = adafruit_rfm9x.RFM9x(spi, cs, reset, 433.0)
print("RFM9x radio ready")

"Not LoRa from here"

"BMP280 Sensor"
# BMP280 comunication start up

i2c = busio.I2C(scl=board.GP15, sda=board.GP14)
bmp280_sensor = adafruit_bmp280.Adafruit_BMP280_I2C(i2c, address=0x76)

# BMP280 sensor readings

def read_temperature():
    return bmp280_sensor.temperature

def read_pressure():
    return bmp280_sensor.pressure

while True:
    ledazul.value = True
    "LoRa"
    rfm9x.send("Hello World, this is a test, why does this not work? im going mad!!!!")
    print("Radio mensage sent")
    "Not LoRa from here"
    ledazul.value = False
    cansat_temperature = read_temperature()
    print("TEMPERATURE:")
    print(cansat_temperature)
    cansat_pressure = read_pressure()
    print("PRESSURE:")
    print(cansat_pressure)
    print(" ")
    time.sleep(2.5)

注：代码除LoRa通信外包含BMP280传感器读取功能，LoRa相关代码位于"LoRa"标记下方。

已尝试的排查措施：

• 焊接天线、更换不同天线
• 修改两端代码（未解决问题）

寻求帮助：

1. 解决接收消息乱码的具体方法
2. 对现有代码的优化建议

内容的提问来源于stack exchange，提问作者Enrique G C