Patent ID: 11942981
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 7:
8. A communication system comprising:
the receiver according to claim 5; and
any one of
a transmitter comprising:
chirp spread circuitry to spread a data signal with a chirp that is a spread code;
a preamble generator to spread a known signal with an up chirp that is a spread code whose frequency increases with time and a down chirp that is a spread code whose frequency decreases with time;
a frame generator to frame a data block that is spread and generated by the chirp spread circuitry and a preamble block that is spread and generated by the preamble generator; and
a space time coder to perform space time code on the data signal, wherein
the chirp spread circuitry spreads the signal subjected to space time code by the space time coder with the chirp, and
the preamble generator performs space time code on the known signal and then spreads the known signal with the up chirp and the down chirp,

a transmitter comprising:
chirp spread circuitry to spread a data signal with a chirp that is a spread code;
a preamble generator to spread a known signal with an up chirp that is a spread code whose frequency increases with time and a down chirp that is a spread code whose frequency decreases with time;
a frame generator to frame a data block that is spread and generated by the chirp spread circuitry and a preamble block that is spread and generated by the preamble generator; and
a space time coder to perform space time code on the data signal, wherein
the chirp spread circuitry spreads the signal subjected to space time code by the space time coder with the chirp,
the preamble generator performs space time code on the known signal and then spreads the known signal with the up chirp and the down chirp, and
the preamble generator spreads a first half of the preamble block with one of the up chirp or the down chirp, and spreads a second half of the preamble block with another one of the up chirp or the down chirp, or

a transmitter comprising:
chirp spread circuitry to spread a data signal with a chirp that is a spread code;
a preamble generator to spread a known signal with an up chirp that is a spread code whose frequency increases with time and a down chirp that is a spread code whose frequency decreases with time;
a frame generator to frame a data block that is spread and generated by the chirp spread circuitry and a preamble block that is spread and generated by the preamble generator; and
a space time coder to perform space time code on the data signal, wherein
the chirp spread circuitry spreads the signal subjected to space time code by the space time coder with the chirp,
the preamble generator performs space time code on the known signal and then spreads the known signal with the up chirp and the down chirp, and
the preamble generator divides the preamble block into a plurality of blocks, and alternately arranges a block spread with the up chirp and a block spread with the down chirp.