卫星链路计算软件Satmaster帮助(5)

Radian Mode

弧度模式

For trigonometrical functions, the expression evaluator may be set to work in radians by selecting the radian mode radio button. The default setting is degree mode.

选择该模式后，三角函数中，算式表达的值为弧度。默认设置为角度模式。

Convert D:M:S: To Degrees Form

度-分-秒转换为度的小数。

This form is used to convert degrees, minutes and seconds to decimal degrees as often used in the satellite industry.

Enter the degrees, minutes and seconds into the separately labelled input fields on the form then click the OK button to view the result. When finished converting click \the form.

这个工具用来转换度-分-秒数据为十进制的小数，这种小数在卫星产业中经常使用。 输入度，分，秒于相应的框，按OK来看结果。计算完成后按Cancel推出该对话框。

Convert Degrees to D:M:S

This form is used to convert decimal degrees to degrees, minutes and seconds.

Enter the decimal value for degrees into the labelled input field on the form then click the OK button to view the result. When finished converting click \这个工具用来转换十进制小数为度-分-秒值。

输入小数于相应的框，按OK来看结果。计算完成后按Cancel推出该对话框。

Estimate Antenna Noise

天线噪声估计

Complete this form to obtain a reasonable estimate for Antenna noise. 输入该表格可以算出一个大概的天线噪声值 详见

Antenna efficiency 天线效率 Frequency 中心频率 Antenna elevation 天线俯仰

Enter the elevation angle to which the antenna is to be set. The accepted range is 1 to 90 degrees 输入天线的俯仰角。可输入的角度为1-90度。

Calculate Noise Figure Form

计算噪声因数

This form is used to obtain a noise temperature, in K, for conversion to an equivalent noise figure in dB. Medium temperature used in the conversion is 290K.

这个表格通过噪声值来计算噪声温度，以开为单位。在这个转换中设定环境温度为290K。

Calculate Noise Temperature Form

计算噪声温度

This form is used to obtain a noise figure, in dB, for conversion to an equivalent noise temperature in K. Ambient temperature used in the conversion is standardized at 290K. 这个表格通过噪声温度计算噪声值。在这个转换中设定环境温度为290K。

Calculate Beamwidth Form

计算波束宽度

This form is used to obtain data in order to calculate an antenna main lobe beamwidth. The beamwidth calculation is based on the uniform illumination condition. By specifying a relative amplitude (-dB) the corresponding beamwidth at that amplitude is calculated. The calculation also depends on frequency and antenna aperture. 这个表格可计算天线的主瓣波束宽度。默认是在标准照明情况下的值。输入一个参考振幅值（-dB为单位？）相应的波束宽度就会被算出。结果和频率和天线尺寸也有关。

Amplitude

振幅

Enter the dB down point in the range -0.1dB to -20dB at which the beamwidth is to be calculated.

输入-0.1dB到 -20dB的振幅，波束宽度根据它进行计算。

Frequency

频率

Enter the centre frequency of the carrier in GHz. For the uplink, typical values are around 6GHz and 14GHz for C and Ku band respectively. For the downlink, values of 4GHz and 12GHz are typical. The accepted range is 1GHz to 50GHz

输入上行载波的中心频率，以Ghz为单位。典型C波段和Ku波段的值为6GHz和14GHz。下行的典型频率为4Ghz和12GHz。可输入的范围为1Ghz到50GHz。

Antenna Aperture

天线口径

Antenna aperture is normally taken as the overall diameter of a parabolic dish, the major dimension if an offset focus antenna. Units are always metric (in metres) to conform to international engineering practice. The lower limit handled is 0.2 metres and the highest 50 metres.

天线口径通常是抛物线天线的直径，偏馈天线的主要直径。单位都是米。最少为0.2米，最大为50米。

Calculate Wavelength Form

计算波长

This form is used to obtain a frequency, in GHz, for conversion to wavelength in metres 这个表格用来通过频率计算波长。

Carsons's Rule Form

卡森法则

This form is used to obtain data in order to estimate the peak, and peak to peak, FM deviation if the RF bandwidth and maximum modulating video frequency is known.

这个表格可以计算峰值频率，峰值到峰值的带宽，和FM的频偏，如果带宽和和视频带宽已知的话。

Digital Bandwidth Calculator

数字通信带宽计算

This module calculates the bandwidth requirements to transmit information data streams. Symbol rate, occupied bandwith, allocated bandwidth and noise bandwidth are calculated for the selected information rate and modulation scheme. 这个模块计算传输数据流所需要的贷款需求。对于一个数据速率和调制方案，相应的符号率，占用带宽，非配带宽和噪声带宽会被计算出来 Information rate 信息速率 Overhead (% information rate) 系统占用带宽 Forward error correction (FEC) code rate 前向纠错 Spreading gain 扩频增益 RS code RS码

(1 + Roll off factor) 1+滚降系数 Carrier spacing factor 载波

Bandwidth allocation step size 带宽分配块大小 详见Carrier and Modulation载波和调制。

Signal Availability Form

信号可用度换算

This form is used to obtain a signal availability figure as a percentage of the worst month for conversion to a percentage of an average year. The latter parameter is assumed for input to the link budget calculation so this facility allows quick conversion if you prefer to work with worst month figures.

For example a signal availability of 99% of the worst month, equates to 99.7% of an average year.

这个表格可以吧最“糟糕的一个月”可用度换算为年平均可用度。后者是链路计算中需要输入的参数。如果你习惯用“糟糕的一个月”数据，这个工具可以方便的转换为年可用度。 比如“糟糕的一个月”信号可用度99%可换算成年可用度99.7%。

Focal Distance Form

焦距换算

This form obtains parameters in order to plot a parabola for a particular …… 此处隐藏：4861字，全部文档内容请下载后查看。喜欢就下载吧 ……