gnuradio笔记[1]-内嵌python代码块
摘要
在GNU Radio中简单使用内嵌python代码块实现输出内容到文件.
超链接
原理简介
GNU Radio简介
[https://wiki.gnuradio.org/index.php?title=What_Is_GNU_Radio]
GNU Radio is a free & open-source software development toolkit that provides signal processing blocks to implement software radios. It can be used with readily-available low-cost external RF hardware to create software-defined radios, or without hardware in a simulation-like environment. It is widely used in research, industry, academia, government, and hobbyist environments to support both wireless communications research and real-world radio systems.
GNU Radio is a framework that enables users to design, simulate, and deploy highly capable real-world radio systems. It is a highly modular, "flowgraph"-oriented framework that comes with a comprehensive library of processing blocks that can be readily combined to make complex signal processing applications. GNU Radio has been used for a huge array of real-world radio applications, including audio processing, mobile communications, tracking satellites, radar systems, GSM networks, Digital Radio Mondiale, and much more - all in computer software. It is, by itself, not a solution to talk to any specific hardware. Nor does it provide out-of-the-box applications for specific radio communications standards (e.g., 802.11, ZigBee, LTE, etc.,), but it can be (and has been) used to develop implementations of basically any band-limited communication standard.
GNU Radio是一个免费开源的软件开发工具包，提供信号处理块来实现软件无线电。它可以与现成的低成本外部RF硬件一起使用，以创建软件定义的无线电，或者在没有硬件的情况下在类似模拟的环境中使用。它广泛应用于研究、工业、学术、政府和业余爱好者环境，以支持无线通信研究和现实世界的无线电系统。
GNU Radio是一个框架，使用户能够设计、模拟和部署高性能的现实无线电系统。它是一个高度模块化的、面向“流图”的框架，带有全面的处理块库，可以很容易地组合起来，制作复杂的信号处理应用程序。GNU Radio已被用于大量的现实无线电应用，包括音频处理、移动通信、跟踪卫星、雷达系统、GSM网络、数字无线电世界等等，所有这些都在计算机软件中。它本身并不是与任何特定硬件通信的解决方案。它也没有为特定的无线电通信标准（如802.11、ZigBee、LTE等）提供开箱即用的应用程序，但它可以（并且已经）用于开发基本上任何带限通信标准的实现。
GNU Radio使用基于流图的可视化方式开发,支持内嵌代码.
python代码块简介
[https://wiki.gnuradio.org/index.php/Embedded_Python_Block]
This block allows you to create a new (custom) block in Python without needing to make and install an Out of Tree (OOT) Module. When you add the block to your flowgraph, the pre-populated code simply takes the input stream and multiplies it by a constant. Note that the structure of this Python block matches the structure of an OOT Python block. It's essentially a Python OOT block built into a grc flowgraph.
"""
Embedded Python Blocks:
Each time this file is saved, GRC will instantiate the first class it finds
to get ports and parameters of your block. The arguments to __init__ will
be the parameters. All of them are required to have default values!
"""
import numpy as np
from gnuradio import gr
class blk(gr.sync_block): # other base classes are basic_block, decim_block, interp_block
"""Embedded Python Block example - a simple multiply const"""
def __init__(self, example_param=1.0): # only default arguments here
"""arguments to this function show up as parameters in GRC"""
gr.sync_block.__init__(
self,
name='Embedded Python Block', # will show up in GRC
in_sig=[np.complex64],
out_sig=[np.complex64]
)
# if an attribute with the same name as a parameter is found,
# a callback is registered (properties work, too).
self.example_param = example_param
def work(self, input_items, output_items):
"""example: multiply with constant"""
output_items[0][:] = input_items[0] * self.example_param
return len(output_items[0])
参数:
The parameters for this block are simply those of your embedded Python block itself.
Note that every parameter needs a default value. For example, in the code above, note line:
def __init__(self, example_param=1.0): # only default arguments here
#If you don't have any parameters, change that line of code to
def __init__(self):
#If you have a vector length equal to a variable of your block, note that the default value must be "hardcoded".
实现
连线
注意
输入输出类型要匹配,如都是byte,否则连线会变成红色.
代码块代码
"""
Embedded Python Block demo
"""
# epy_block_0.py
# created 10/17/2019
import numpy as np
from gnuradio import gr
import pmt
textboxValue = ""
class my_sync_block(gr.sync_block):
"""
reads input from a message port
outputs text
"""
def __init__(self):
gr.sync_block.__init__(self,
name = "Embedded Python demo",
in_sig = None,
out_sig = [np.byte])
self.message_port_register_in(pmt.intern('msg_in'))
self.message_port_register_out(pmt.intern('clear_input'))
self.set_msg_handler(pmt.intern('msg_in'), self.handle_msg)
def handle_msg(self, msg):
global textboxValue
textboxValue = pmt.symbol_to_string (msg)
# print (textboxValue)
def work(self, input_items, output_items):
global textboxValue
# get length of string
_len = len(textboxValue)
if (_len > 0):
# terminate with LF
textboxValue += "\n"
_len += 1
# store elements in output array
for x in range(_len):
output_items[0][x] = ord(textboxValue[x])
textboxValue = ""
self.message_port_pub(pmt.intern('clear_input'), pmt.intern(''))
return (_len)
else:
return (0)
效果
