GMSK (Guassian Minimum Shift Keying) modulation device and method

Abstract

The invention discloses GMSK (Guassian Minimum Shift Keying) modulation device and method. The GMSK modulation device comprises a first data processing module, a first data generation module, a second data generation module, a data acquisition module and a second data processing module. Compared with the prior art, the GMSK modulation device provided by the embodiment of the invention does not use an accumulated phase bypass of a baseband signal as an address acquiring modulation signal data inside a lookup table, the lookup table only stores the modulation signal data related to the real-time phase information of the baseband signal, the final modulation signal data of the baseband signal is obtained by the modulation signal data looked up from the lookup table through angle rotation, therefore the ROM (Read Only Memory) occupying quantity of the lookup table is greatly reduced, the less capacity of the storage space of the ROM is, the smaller volume of the ROM is, and then the smaller area of an occupied chip is, thus the GMSK modulation device is more suitable for an super-large-scale integration.

Description

technical field [0001] The present application relates to the technical field of mobile communication, in particular to a GMSK modulation device and method. Background technique [0002] The basic working principle of GMSK (Gaussian-filtered Minimum Shift Keying, Gaussian-filtered Minimum Shift Keying) modulation is to shape the baseband signal through a Gaussian filter first, and then perform minimum frequency shift keying (MSK) modulation, because the spectrum of GMSK modulation The characteristic is better than the spectrum characteristic of MSK signal, so it is widely used in the field of mobile communication. [0003] The key to GMSK modulation is to determine the phase of the final output modulated signal according to the input bit. [0004] At present, the table look-up method is mainly used to realize GMSK modulation, and the modulated signal can be expressed as s(t)=Acos(2pf c t+j(t)), -? t<+□. j(t) can be expressed as Among them, a i is the value of the i...

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Problems solved by technology

[0006] In the process of realizing the present application, the inventor finds that there are at least the following problems in the prior art: the look-up table in the look-up table method for realizing GMSK modulation in the prior art still needs to occupy a large amount of ROM space, and the larger the ROM space, the larger the volume. Larger, so the occupied chip area is also larger, not suitable for application in VLSI

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