Transmission device and transmission method

A transmission device, comprising:

• a weighting synthesizer that generates a first precoded signal and a second precoded signal by performing a precoding process on a first baseband signal and a second baseband signal, respectively;
• a first pilot inserter that inserts a pilot signal into the first precoded signal;
• a first phase changer that applies a phase change of i×Δλ to the second precoded signal, depending on a communications scheme, where i is a symbol number and an integer that is greater than or equal to 0;
• a second pilot inserter that inserts a pilot signal into the second precoded signal applied with the phase change;
• and
• a second phase changer that applies a phase change to the second precoded signal applied with the phase change and inserted with the pilot signal, depending on the communications scheme,
• wherein Δλ satisfies π/2 radians <Δλ<π radians or π radians <A<3π/2 radians,
• when the communications scheme is an orthogonal frequency division multiplexing (OFDM) scheme, the first phase changer and the second phase changer apply a phase change, and
• when the communications scheme is a single-carrier scheme, at least one of the first phase changer and the second phase changer does not apply a phase change.