Traveling wave power combiner and radio base station

A power combiner, comprising:

• a plurality of power amplifiers which are connected in parallel and even-numbered;
• a plurality of branch circuits for respectively distributing input power to said plurality of power amplifiers;
• and
• a plurality of combiners for combining respective output power of said plurality of power amplifiers;
• wherein in the case of any one of such combinations as to equalize electric lengths of transmission lines for connecting between adjacent two power amplifiers selected from said plurality of power amplifiers and equalize electric lengths of transmission lines for connecting between non-adjoining two power amplifiers from said plurality of power amplifiers, said combinations being established said plurality of power amplifiers, said electric lengths allowing the establishment of said any one of said combinations take λ/2i (where λ=wavelength of fundamental wave, and i=positive integer).

A linearized power amplifier, comprising:

• a main power amplifier for amplifying a main signal;
• an error signal detection circuit for combining the main signal amplified by said main power amplifier with the pre-amplification main signal to thereby extract an error signal;
• an error signal amplifier for amplifying the error signal;
• a distortion elimination circuit for combining said amplified error signal with said amplified main signal to thereby eliminate distortion of said amplified main signal;
• and
• a control circuit for controlling said error detection circuit and said distortion elimination circuit;
• wherein said main power amplifier has a plurality of power amplifiers which are even-numbered, a plurality of series-connected branch circuits for respectively distributing input power to said plurality of power amplifiers, and a plurality of series-connected combiners for combining respective output power of said plurality of power amplifiers, and in the case of any one of such combinations as to equalize electric lengths of transmission lines for connecting between two power amplifiers selected from said plurality of power amplifiers, said combinations each being established by using all of said plurality of power amplifiers once, said electric lengths at which said any one of said combinations is established, take λ/2i (where λ=wavelength of fundamental wave, and i=positive integer);
• whereby the main signal amplified by said main power amplifier is combined with said pre-amplification main signal without being processed via a harmonic elimination filter.

A radio base station, comprising:

• modulation demodulation equipment for converting each of signals lying within a base band to each of signals lying within a carrier frequency band;
• a main power amplifier for amplifying the signal lying in said carrier frequency band;
• an error signal detection circuit for combining the signal amplified by said main power amplifier, which is lying within the carrier frequency band, and the pre-amplification signal lying within the carrier frequency band to thereby extract an error signal;
• an error signal amplifier for amplifying the error signal;
• a distortion elimination circuit for combining said amplified error signal with said amplified signal lying within the carrier frequency band to thereby eliminate distortion of said amplified signal lying within the carrier frequency band;
• and
• a control circuit for controlling said error signal detection circuit and said distortion elimination circuit;
• and
• an array antenna for outputting the amplified signal lying within the carrier frequency band as a radio wave having directivity;
• wherein said main power amplifier has a plurality of power amplifiers which are even-numbered, a plurality of series-connected branch circuits for respectively distributing input power to said plurality of power amplifiers, and a plurality of series-connected combiners for combining respective output power of said plurality of power amplifiers, and in the case of any one of such combinations as to equalize electric lengths of transmission lines for connecting between two power amplifiers selected from said plurality of power amplifiers, said combinations each being established by using all of said plurality of power amplifiers once, said electric lengths at which said any one of said combinations is established, take λ/2i (where λ=wavelength of fundamental wave, and i=positive integer);
• whereby the signal amplified by said main power amplifier lying within the carrier frequency band is combined with said pre-amplification signal lying within the carrier frequency band without being processed via a harmonic elimination filter.

A power combiner, comprising:

• a plurality of power amplifiers which are even-numbered;
• a plurality of series-connected branch circuits for respectively distributing input power to said plurality of power amplifiers;
• a plurality of series-connected combiners for combining respective output power of said plurality of power amplifiers;
• open stubs respectively having electric lengths of λ/12 (where λ=wavelength of a fundamental wave), which are provided at matching terminators of said plurality of combiners;
• and
• inductors coupled in parallel with said open stubs respectively;
• wherein in the case of any one of such combinations as to equalize electric lengths of transmission lines for connecting between two power amplifiers selected from said plurality of power amplifiers, said combinations each being established by using all of said plurality of power amplifiers once, said electric lengths at which said any one of said combinations is established, take λ/2i (where i=positive integer).