In-band on-channel system with digital frequency spectrum dynamic access

Abstract

The invention discloses an in-band on-channel system with digital frequency spectrum dynamic access. The in-band on-channel system comprises an analog FM exciter module, the analog FM exciter module carries out up-conversion on input real-time sound signals into carrier frequency, and the output signals of the analog FM exciter module are in coupling with digital modulating signals adjusted in real time through certain delay, and are transmitted to an antenna to be sent through a feeder line. The digital modulating signals adjusted in real time are obtained through the following modules, an FM signal generating module carries out FM modulation on the analog sound signals, the modulated signals calculate the digital frequency spectrum corresponding to the FM modulating signals through a digital frequency spectrum dynamic algorithm module, the number of subcarriers corresponding to the digital frequency spectrum is checked through a digital frequency spectrum adjusting module, and digital audio achieves the OFDM modulation of the digital signals through a digital signal modulator according to the calculated number of the subcarriers. A self-adaption adjustment module between the analog sound signals and the digital signal modulator is added, the transmission bandwidth of the digital signals is dynamically adjusted according to the real-time distribution state of the analog signals, on the premise of enabling the listening quality of audiences not to be reduced, the available frequency spectrum of the digital signals is improved, and the transmission capacity of the digital signals under a mixed mode is improved.

Description

technical field [0001] The invention relates to a wireless communication system, in particular to an in-band co-frequency system for dynamic access of digital spectrum. Background technique [0002] Digitization of broadcasting is a hot issue in domestic and foreign technical research at present, and digital sound broadcasting in my country is still in the research stage. In the HD Radio standard of the United States, the "in-band co-frequency (IBOC)" technology adopted enables digital broadcasting to use the same carrier frequency as the current analog broadcasting, without breaking the existing frequency planning, and can realize smooth broadcasting from analog to digital transition. Under the premise of not affecting the existing analog broadcasting, the IBOC technology uses the existing analog broadcasting channels to provide high-definition digital voice broadcasting and data services, which is in line with my country's national conditions. [0003] In the hybrid mode...

AI Technical Summary

Problems solved by technology

[0007] When the digital signal dynamically adjusts the spectrum position according to the change of the analog signal, an inevitable question that needs to be discussed is whether the dynamic allocation of the spectrum position of the digital signal will deteriorate the user's listening quality

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