Receiving device, receiving method, program, and receiving system
View Patent ↗This technique relates to a receiving device, a receiving method, a program, and a receiving system that are designed to reduce circuit size. A receiving device of one aspect of this technique includes: a de-mapping unit that receives a symbol signal generated by performing mapping on a first branch signal and a second branch signal indicating information about the same transmission target, and performs de-mapping on the symbol signal by a hard decision; a selecting unit that selects, in accordance with a reception state, one signal from the first branch signal and the second branch signal obtained through the de-mapping; and a decoding unit that decodes the information about the transmission target based on the one signal. This technique can be applied to receivers that receive OFDM signals compliant with DVB-C2.
1. A receiving device comprising:
a de-mapping unit configured to receive a symbol signal generated by performing mapping on a first branch signal and a second branch signal indicating information about a transmission target, and perform de-mapping on the symbol signal by a hard decision;
a selecting unit configured to receive the first branch signal and the second branch signal, and to receive a reception state signal from a comparing unit, the selecting unit providing a selected signal by selecting either the first branch signal or the second branch signal depending upon the reception state signal;
a decoding unit configured to decode the information about the transmission target based on the selected signal;
a cyclic shifting unit configured to perform cyclic shifting on the second branch signal obtained through the de-mapping, the cyclic shifting being performed in reverse order of cyclic shifting order in a transmitting device, and
the selecting unit selects a signal from the second branch signal indicating predetermined bits excluding a bit located in a predetermined region starting from a beginning of a sequence after the cyclic shifting performed by the cyclic shifting unit, and the first branch signal indicating the predetermined bits, the predetermined bits being of a plurality of bits indicated by the second branch signal obtained through the de-mapping, wherein
the cyclic shifting is performed on the second branch signal in the transmitting device that transmits the symbol signal.
2. The receiving device according to claim 1 , wherein the symbol signal is a signal of one of a Forward Error Correction Frame Header and a Preamble Header compliant with Digital Video Broadcasting for Cable 2.
3. The receiving device according to claim 1 , wherein the selecting unit selects the first branch signal as a signal indicating the bit located in the predetermined region.
4. The receiving device according to claim 1 , wherein
the symbol signal is a signal of the Forward Error Correction Frame Header compliant with Digital Video Broadcasting for Cable 2, and
the selecting unit,
before a position of the Forward Error Correction Frame Header is detected, selects a signal from the first branch signal and the second branch signal indicating the predetermined bits, and
after the position of the Forward Error Correction Frame Header is detected, selects a signal from the first branch signal and the second branch signal indicating the plurality of bits.
5. A receiving method comprising the steps of:
receiving a symbol signal generated by performing mapping on a first branch signal and a second branch signal indicating information about a same transmission target, and performing de-mapping on the symbol signal by a hard decision;
receiving the first branch signal, the second branch signal, and a reception state signal from a comparing unit and selecting either the first branch signal or the second branch signal depending upon the reception state signal;
decoding the information about the transmission target based on the selected signal;
performing cyclic shifting on the second branch signal obtained through the de-mapping, the cyclic shifting being performed in reverse order of cyclic shifting order in a transmitting device, and
selecting a signal from the second branch signal indicating predetermined bits excluding a bit located in a predetermined region starting from a beginning of a sequence after the cyclic shifting performed by the cyclic shifting unit, and the first branch signal indicating the predetermined bits, the predetermined bits being of a plurality of bits indicated by the second branch signal obtained through the de-mapping, wherein
the cyclic shifting is performed on the second branch signal in the transmitting device that transmits the symbol signal.
6. The receiving method according to claim 5 , wherein the symbol signal is a signal of one of a Forward Error Correction Frame Header and a Preamble Header compliant with Digital Video Broadcasting for Cable 2.
7. The receiving method according to claim 5 , wherein the selecting unit selects the first branch signal as a signal indicating the bit located in the predetermined region.
8. The receiving method according to claim 5 , wherein the symbol signal is a signal of the Forward Error Correction Frame Header compliant with Digital Video Broadcasting for Cable 2, and the selecting unit,
before a position of the Forward Error Correction Frame Header is detected, selects a signal from the first branch signal and the second branch signal indicating the predetermined bits, and,
after the position of the Forward Error Correction Frame Header is detected, selects a signal from the first branch signal and the second branch signal indicating the plurality of bits.
9. A non-transitory computer readable medium storing program code being executable by a processor of a device to perform operations comprising:
receiving a symbol signal generated by performing mapping on a first branch signal and a second branch signal indicating information about a same transmission target, and performing de-mapping on the symbol signal by a hard decision;
receiving the first branch signal, the second branch signal, and a reception state signal from a comparing unit and selecting either the first branch signal or the second branch signal depending upon the reception state signal;
decoding the information about the transmission target based on the selected signal;
performing cyclic shifting on the second branch signal obtained through the de-mapping, the cyclic shifting being performed in reverse order of cyclic shifting order in a transmitting device, and
selecting a signal from the second branch signal indicating predetermined bits excluding a bit located in a predetermined region starting from a beginning of a sequence after the cyclic shifting is performed, and the first branch signal indicating the predetermined bits, the predetermined bits being of a plurality of bits indicated by the second branch signal obtained through the de-mapping, wherein
the cyclic shifting is performed on the second branch signal in the transmitting device that transmits the symbol signal.
10. The non-transitory computer readable medium of claim 9 , wherein the symbol signal is a signal of one of a Forward Error Correction Frame Header and a Preamble Header compliant with Digital Video Broadcasting for Cable 2.
11. The non-transitory computer readable medium of claim 9 , wherein the selecting unit selects the first branch signal as the signal indicating the bit located in the predetermined region.
12. A receiving system comprising:
a receiving unit configured to receive a signal transmitted via a transmission channel;
a demodulating unit configured to perform a demodulating operation on the signal received by the receiving unit;
a signal processing unit configured to perform signal processing on data demodulated by the demodulating unit, and acquire transmission target data; and
an output unit configured to output the transmission target data acquired by the signal processing unit,
the signal processing unit including:
a de-mapping unit configured to receive a symbol signal generated by performing mapping on a first branch signal and a second branch signal indicating information about a transmission target, and perform de-mapping on the symbol signal by a hard decision;
a selecting unit configured to receive the first branch signal and the second branch signal, and to receive a reception state signal from a comparing unit, the selecting unit providing a selected signal by selecting either the first branch signal or the second branch signal depending upon the reception state signal;
a decoding unit configured to decode the information about the transmission target based on the selected signal;
a cyclic shifting unit configured to perform cyclic shifting on the second branch signal obtained through the de-mapping, the cyclic shifting being performed in reverse order of cyclic shifting order in a transmitting device, and
the selecting unit selects a signal from the second branch signal indicating predetermined bits excluding a bit located in a predetermined region starting from a beginning of a sequence after the cyclic shifting is performed, and the first branch signal indicating the predetermined bits, the predetermined bits being of a plurality of bits indicated by the second branch signal obtained through the de-mapping, wherein the cyclic shifting is performed on the second branch signal in the transmitting device that transmits the symbol signal.
13. The receiving system according to claim 12 , wherein the symbol signal is a signal of one of a Forward Error Correction Frame Header and a Preamble Header compliant with Digital Video Broadcasting for Cable 2.
14. The receiving system according to 12 , wherein the selecting unit selects the first branch signal as a signal indicating the bit located in the predetermined region.
15. The receiving system according to 12 , wherein the symbol signal is a signal of a Forward Error Correction Frame Header compliant with Digital Video Broadcasting for Cable 2, and
the selecting unit,
before a position of the Forward Error Correction Frame Header is detected, selects a signal from the first branch signal and the second branch signal indicating the predetermined bits, and,
after the position of the Forward Error Correction Frame Header is detected, selects a signal from the first branch signal and the second branch signal indicating the plurality of bits.