Abstract:
In order to transmit a combination of modulated analog and digital signals in which a digital data signal (D 1 ) is modulated by means of singlecarrier quadrature amplitude modulation (QAM) or by means of multicarrier Orthogonal Frequency Division Multiplex (OFDM) modulation and an analog signal (A 1 ) is modulated by means of single side band modulation (SSB), a singlecarrier or multicarrier quadrature amplitude base modulation of the digital data signal (D 1 ) and an SSB base modulation of the analog signal (A 1 ), is performed. Corresponding components of the modulated and optionally upsampled digital ( u m I , o m I , u m Q ,O m Q )and analog ( s m I , s m Q ) signals are added, and a carrier frequency modulation (4) of the added components is performed. In a receiver, the same carrier frequency demodulator (8) is used for the superimposed modulated analog and digital signals, which then are base band demodulated separately (5, 6, 7). The invention reduces the total computational effort for modulating the digital and analog signals by performing the carrier frequency modulation or demodulation only once.
Abstract:
The present invention proposes the use of transparent transmission of teleprotection commands in the form of GOOSE or GSSE messages, as defined by the Generic Substation Event (GSE) class model by the standard IEC 61850, between substations combined with Channel Supervision and Monitoring (CSM) equivalent to CSM offered by conventional teleprotection equipment. This approach avoids the disadvantage of non-transparent transmission when using the gateway approach and of the lack of the CSM functionality when using the tunnelling approach.
Abstract:
In order to transmit a combination of modulated analog and digital signals in which a digital data signal (D1) is modulated by means of singlecarrier quadrature amplitude modulation (QAM) or by means of multicarrier Orthogonal Frequency Division Multiplex (OFDM) modulation and an analog signal (A1) is modulated by means of single side band modulation (SSB), a singlecarrier or multicarrier quadrature amplitude base modulation of the digital data signal (D1) and an SSB base modulation of the analog signal (A1), is performed. Corresponding components of the modulated and optionally upsampled digital (umI, omI ,umQ,OmQ)and analog (smI, smQ) signals are added, and a carrier frequency modulation (4) of the added components is performed. In a receiver, the same carrier frequency demodulator (8) is used for the superimposed modulated analog and digital signals, which then are base band demodulated separately (5, 6, 7). The invention reduces the total computational effort for modulating the digital and analog signals by performing the carrier frequency modulation or demodulation only once.
Abstract:
In order to transmit a combination of modulated analog and digital signals in which a digital data signal (D1) is modulated by means of singlecarrier quadrature amplitude modulation (QAM) or by means of multicarrier Orthogonal Frequency Division Multiplex (OFDM) modulation and an analog signal (A1) is modulated by means of single side band modulation (SSB), a singlecarrier or multicarrier quadrature amplitude base modulation of the digital data signal (D1) and an SSB base modulation of the analog signal (A1), is performed. Corresponding components of the modulated and optionally upsampled digital (umI, omI ,umQ,OmQ)and analog (smI, smQ) signals are added, and a carrier frequency modulation (4) of the added components is performed. In a receiver, the same carrier frequency demodulator (8) is used for the superimposed modulated analog and digital signals, which then are base band demodulated separately (5, 6, 7). The invention reduces the total computational effort for modulating the digital and analog signals by performing the carrier frequency modulation or demodulation only once.