GNURadio自定义Python OOT块导入失败问题求助

问题描述 #

我是GNURadio自定义OOT块新手，正在制作查找表（lookup table）块，按官方教程操作。模块编译安装成功，文件安装在/usr/local/lib/目录下，但在GNU Radio Companion中刷新块并运行后，出现ImportError：无法从gnuradio导入DABPhaseRef。尝试设置PYTHONPATH后问题仍未解决，使用Manjaro Linux系统。

错误信息 #

Generating: '/home/matterhorn/gnu_radio/lookup_test.py'

Executing: /usr/bin/python3 -u /home/matterhorn/gnu_radio/lookup_test.py

Traceback (most recent call last):
  File "/home/matterhorn/gnu_radio/lookup_test.py", line 27, in <module>
    from gnuradio import DABPhaseRef
ImportError: cannot import name 'DABPhaseRef' from 'gnuradio' (/usr/lib/python3.10/site-packages/gnuradio/__init__.py)

>>> Done (return code 1)

自定义块Python代码（lookupTable.py） #

#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# Copyright 2023 Staš Bucik.
#
# SPDX-License-Identifier: GPL-3.0-or-later
#


import numpy as np
from gnuradio import gr

class lookupTable(gr.sync_block):
    """
    docstring for block lookupTable
    """
    def __init__(self):
        gr.sync_block.__init__(self,
            name="lookupTable",
            in_sig=None,
            out_sig=[(np.complex64, 2048)])
        
        self.kinTable = # long lookup table 
        
        self.timePhaseTable = # long lookup table 
        
        self.table = []
        for k in range(-1024, 1024):
            '''if k < -768 or k > 768 or k == 0:
                table[k + 1024] = 0. + 0.j
            else:
                kin = self.getKINParams(k)
                h = self.timePhaseTable[kin[1], k - kin[0]]
                phase = np.pi * 0.5 * (h + kin[2])
                table[k + 1024] = np.exp(1.j * phase)'''
            table[k + 1024] = k + 0.j

    def getKINParams(self, k):
        for row in self.kinTable:
            if k >= row[0] and k <= row[1]:
                return row[2:]
        raise Exception("No KIN parameters found!")

    def work(self, input_items, output_items):
        output_items[0] = self.table
        return len(output_items[0])

GRC块配置YAML文件（DABPhaseRef_lookupTable.block.yml） #

id: DABPhaseRef_lookupTable
label: lookupTable
category: '[DABPhaseRef]'

templates:
  imports: from gnuradio import DABPhaseRef
  make: DABPhaseRef.lookupTable()

#  Make one 'inputs' list entry per input and one 'outputs' list entry per output.
#  Keys include:
#      * label (an identifier for the GUI)
#      * domain (optional - stream or message. Default is stream)
#      * dtype (e.g. int, float, complex, byte, short, xxx_vector, ...)
#      * vlen (optional - data stream vector length. Default is 1)
#      * optional (optional - set to 1 for optional inputs. Default is 0)


outputs:
- label: out0
  domain: stream
  dtype: complex
  vlen: 2048

#  'file_format' specifies the version of the GRC yml format used in the file
#  and should usually not be changed.
file_format: 1

安装日志 #

Install the project...
-- Install configuration: "Release"
-- Up-to-date: /usr/local/lib/cmake/gnuradio-DABPhaseRef/gnuradio-DABPhaseRefConfig.cmake
-- Up-to-date: /usr/local/include/gnuradio/DABPhaseRef/api.h
-- Up-to-date: /usr/local/lib/python3.10/site-packages/gnuradio/DABPhaseRef/__init__.py
-- Up-to-date: /usr/local/lib/python3.10/site-packages/gnuradio/DABPhaseRef/lookupTable.py
-- Installing: /usr/local/lib/python3.10/site-packages/gnuradio/DABPhaseRef/__init__.pyc
-- Installing: /usr/local/lib/python3.10/site-packages/gnuradio/DABPhaseRef/lookupTable.pyc
-- Installing: /usr/local/lib/python3.10/site-packages/gnuradio/DABPhaseRef/__init__.pyo
-- Installing: /usr/local/lib/python3.10/site-packages/gnuradio/DABPhaseRef/lookupTable.pyo
-- Up-to-date: /usr/local/share/gnuradio/grc/blocks/DABPhaseRef_lookupTable.block.yml

解决方案 #

1. 确保Python路径包含/usr/local的site-packages #

Manjaro中Python默认优先加载/usr/lib下的gnuradio，而自定义模块安装在/usr/local/lib/python3.10/site-packages下。临时修复可在终端运行：

export PYTHONPATH="/usr/local/lib/python3.10/site-packages:$PYTHONPATH"

之后再启动GNU Radio Companion运行流图。

若要永久生效，将上述命令添加到shell配置文件（_/.bashrc、/.zshrc等），再重新加载配置：

source ~/.bashrc  # bash用户
# 或
source ~/.zshrc   # zsh用户

2. 检查DABPhaseRef模块的__init__.py #

打开/usr/local/lib/python3.10/site-packages/gnuradio/DABPhaseRef/__init__.py，确保正确导出lookupTable类，添加以下内容：

from .lookupTable import lookupTable

__all__ = ['lookupTable']

这样才能通过from gnuradio import DABPhaseRef后调用DABPhaseRef.lookupTable()。

3. 验证模块导入是否正常 #

在终端启动Python3，执行以下命令测试：

import sys
sys.path.insert(0, "/usr/local/lib/python3.10/site-packages")
from gnuradio import DABPhaseRef
# 测试实例化块
block = DABPhaseRef.lookupTable()

若无报错，说明模块导入正常，此时再运行GRC流图即可。

4. 修复Python代码中的索引错误 #

lookupTable类中self.table初始化为空列表，直接用table[k + 1024]赋值会触发索引错误，需先初始化列表长度：

self.table = [0+0j] * 2048  # k从-1024到1023，共2048个元素

内容的提问来源于stack exchange，提问作者Staš Bucik