Gaussian filtered minimum shift keying (GSMK) digital demodulation error metering method and system

A technology for digital demodulation and metering systems, which is applied in phase-modulated carrier systems, baseband system components, and shaping networks in transmitters/receivers. It can solve the error cycle and accumulation, and is difficult to ensure accuracy and reliability And other issues

CN102325106AInactive Publication Date: 2012-01-18TELECOMM METROLOGY CENT OF MINIST OF IND & INFORMATION TECH +1
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2012-01-18
Estimated Expiration
Not applicable · inactive patent

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Abstract

The invention relates to a Gaussian filtered minimum shift keying (GSMK) digital demodulation error metering method and a system. The metering method comprises the steps of: 1) taking a phase modulation (PM) signal as a standard GSMK signal; 2) setting 0.5Rs difference value delta f by setting the modulation frequency and standard of the PM signal, and setting the capture length N of a vector signal analyzer at the same time, wherein the N and the delta f satisfy a certain constraint relation; 3) establishing an analytic relation between the frequency parameter delta f and a modulation error parameter; and 4) comparing the calculable digital modulation error parameter with a value measured by the vector signal analyzer to realize the metering and calibration of a GMSK demodulation error parameter. The metering system provided by the invention comprises an analog signal generator, a power divider, a tunable receiver and a measured vector signal analyzer. The method and the system provided by the invention can be used for metering and calibrating the digital demodulation errors of vector signal analyzers and mobile communication comprehensive testers with a GMSK analysis and demodulation function, and can be widely used.
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Description

Technical field

[0001] The present invention relates to wireless communication and radio and television information transmission technology, in particular to the measurement of GMSK signal modulation errors used in the design of second-generation mobile communication systems. Background technique

[0002] Definitions of acronyms and key terms

[0003] PhaseErrRms, the root mean square value of phase error

[0004] PhaseErrPeak, phase error peak

[0005] EvmRms, the root mean square value of the error vector magnitude

[0006] EvmPeak Error vector magnitude peak

[0007] MagErr amplitude error

[0008] PM signal. Phase modulation signal

[0009] Digital modulation signal has become an important cornerstone of the information society and the main carrier of information transmission. The most typical is the application in wireless communication and broadcast television systems, such as the GMSK signal used in the second-generation mobile communication system. The number of mobile phone use...

Examples

Embodiment Construction

[0044] In order to make the objectives, technical solutions and advantages of the present invention clearer, the following further describes the present invention in detail in conjunction with specific embodiments and accompanying drawings.

[0045] The symbol rate of GMSK signal is R s , And the symbol sequence is 101010..., then when the Gaussian filter BT = 0.3, the GMSK signal is a sinusoidal phase modulation signal, the modulation frequency is 0.5R s , And the modulation index is 0.2431. This conclusion is the basis for subsequent error construction and traceability. This conclusion will be proved below. Briefly prove the flow chart such as figure 2 Shown.

[0046] Such as figure 2 As shown, the baseband signal g(t) corresponding to the sequence of 10101 is a bipolar square wave pulse, and the pulse width is the symbol period T of GMSK s , The Fourier series form of this waveform is:

[0047] g ( t ) = R s π { sin [ 2 π ( R s 2 )...