Patent ID: 9625289
Date: 2017-04-18
CPC Classifications: G01D,H04B

Claim:
1. A calibration method of modulation power for a DVB-H (Digital Video Broadcasting-Handheld) test apparatus performed by a computer having a calibration program installed therein and connected to a power meter of the DVB-H test apparatus, comprising: (a) commanding the DVB-H test apparatus to output continuous waves having frequencies from a start frequency to a stop frequency, wherein each interval between adjacent frequencies is equal to a frequency step, the continuous waves having a preset power level; (b) receiving an actual power level of each of the continuous waves from the power meter, obtaining a continuous wave power offset which is a difference between the actual power level and the preset power level, and storing the continuous wave power offset in a power offset table; and (c) commanding the DVB-H test apparatus to output modulated waves, each of which carries data on a continuous wave having a frequency within a range from the start frequency to the stop frequency, receiving an actual output power level of each of the modulated waves from the power meter, obtaining the modulation power offset between the continuous wave and the modulated wave at each frequency among the frequencies from the start frequency to the stop frequency, and thereafter commanding the DVB-H test apparatus to output each modulated wave whose power level is equal to a total power level obtained by adding the preset power level, the continuous wave power offset stored in the power offset table and the modulation power offset so as to obtain an expected power loss at a cable for each modulated wave based on an actual power loss at the cable for each continuous wave wherein the cable is connected between the DVB-H test apparatus and an RF (radio frequency) connector.