CIC补偿插装器
使用FIR插造器补偿CIC过滤器
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Filtering/Filter Designs
dspfdesign
描述
TheCIC补偿插装器block uses an FIR polyphase interpolator as the compensation filter. CIC compensation interpolators are multirate FIR filters that can be cascaded with CIC interpolators to mitigate the drawbacks of the CIC filters.
CIC interpolation filters are used in areas that require high interpolation. These filters are popular in ASICs and FPGAs, since they do not have any multipliers. CIC filters have two drawbacks:
CIC过滤器具有大小响应,导致Passband区域下垂。这种大小响应是:
M- 差延迟
n- 阶段数
ω— Normalized angular frequency
CIC过滤器具有较宽的过渡区域。
The compensation interpolator filters have an inverse sinc passband response to correct for the CIC droop, and they have a narrow transition width.
这个块带来了dsp.CICCompensationInterpolator
System object™ to the Simulink®环境。
Dialog Box
主选项卡
- 费率变化因子
-
CIC滤波器要补偿的速率变化因子,指定为正标性整数。默认值为
2
。 - 部分数量
-
Number of integrator and comb sections of the CIC filter to be compensated, specified as a positive scalar integer. The default is
2
。 - 差延迟
-
在CIC滤波器的每个梳子部分中使用的延迟值被补偿,指定为正标准量。默认值为
1
。
- Interpolation factor
-
补偿器的插值因子,指定为正标性整数。默认值是
2
。 - Minimum order filter design
-
When you select this check box, the block designs filters with the minimum order that meets the specifications for passband frequency, stopband frequency, passband ripple, and stopband attenuation. When you clear this check box, the block designs filters with the order that you specify in过滤订单。
默认情况下,选择此复选框。
- 过滤订单
-
补偿过滤器的顺序,指定为正标准级数。默认值为
12
。 - Passband edge frequency (Hz)
-
补偿滤波器的Passband边缘频率,指定为Hz中的真实正标量。Passband edge frequency (Hz)must be less thanFs/2, whereFsis the output sample rate. The default is
100000
。 - Stopband edge frequency (Hz)
-
Stopband edge frequency of the compensation filter, specified as a real positive scalar in hertz.Stopband edge frequency (Hz)must be less thanFs/2, whereFsis the output sample rate. The default is
400000
。 - Passband Ripple(DB)
-
Passband ripple of compensation filter, specified as a real positive scalar in dB. The default is
0.1
。 - 停止带衰减(DB)
-
补偿过滤器的停止带衰减,指定为DB中的真实正标量。默认值为
60
。 - Inherit sample rate from input
-
When you select this check box, the block inherits its sample rate from the input signal. When you clear this check box, you must specify the sample rate in输入样本率(Hz)。
- 输入样本率(Hz)
-
输入sample rate, specified as a scalar in Hz. The default is
600000
。 - View Filter Response
-
Opens the Filter Visualization Tool FVTool and displays the magnitude/phase response of theCIC补偿插装器。响应基于“块”对话框参数。对这些参数的更改更新FVTool。
To update the magnitude response while FVTool is running, modify the dialog box parameters and clickApply。
- 模拟使用
-
Type of simulation to run. You can set this parameter to:
代码生成
(默认)Simulate model using generated C code. The first time you run a simulation, Simulink generates C code for the block. The C code is reused for subsequent simulations, as long as the model does not change. This option requires additional startup time but provides faster simulation speed than
解释执行
。解释执行
Simulate model using the MATLAB®interpreter. This option shortens startup time but has slower simulation speed than
代码生成
。
Data Types Tab
- 圆形的ing mode
-
圆形的ing method for the output fixed-point operations. The rounding methods are
Ceiling
,收敛
,地面
,Nearest
,圆形的
,最简单
, 和Zero
。默认值为地面
。 - Coefficients
-
Fixed-point data type of the coefficients, specified as one of the following:
FIXDT(1,16)
(默认) - 签名的定点数据类型的单词长度16
,具有二元点缩放。该块以从系数值自动确定分数长度,以使系数占据最大代表范围而不会溢出。fixdt(1,16,0)
- 单词长度的签名定点数据类型16
,分数长度0
。您可以将分数长度更改为任何其他整数值。- 通过使用评估数据类型对象的表达式来指定系数数据类型,例如数字类型(
fixdt
([]
,16
,15
),指定系数数据类型。将此数据类型的符号模式指定为[]
或真实。刷新数据类型
— Refreshes to the default data type.
点击Show data type assistantbutton要显示数据类型助手,这可以帮助您设置阶段输入参数。
See使用数据类型指定数据类型的助理(Simulink)for more information.
万博1manbetx支持的数据类型
Port | 万博1manbetx支持的数据类型 |
---|---|
输入 |
|
Output |
|
See Also
dsp.CICCompensationInterpolator |
DSP System Toolbox |
CIC Compensation Decimator | DSP System Toolbox |
算法
The response of a CIC filter is given by:
R,D, 和N是速率变化因子,差分延迟和CIC滤波器的部分数量。
After decimation, the cic response has the form:okay
最后一个响应的归一化版本是CIC补偿器需要补偿的响应。因此,CIC补偿器的通过响应应采用以下表格:
whereωpis the passband frequency of the CIC compensation filter.
请注意ω/2R≪π,先前的方程式hciccomp(ω) can be simplified using the fact that sin(x) ≅x:
先前的方程是与CIC滤波器的真实逆过带响应的逆sinc近似。