OFDM transceiver apparatus

• US 20050190848A1
• Filed: 03/30/2005
• Published: 09/01/2005
• Est. Priority Date: 12/19/2002
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Iwamatsu, Takanori, Kobayashi, Mitsuo, Ohkawa, Shinya, Kiyanagii, Hiroyuki
• Granted Patent: US 7,551,678 B2
• Time in Patent Office: Days
• US Class Current: 375/260
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity
• CPC Class Codes: H04L 27/2626 Arrangements specific to the transmitter only
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04L 27/2657 Carrier synchronisation

Abstract

In an OFDM transmitter apparatus for transmitting transmit signals, which are output from first and second OFDM transmit circuits, utilizing two mutually orthogonal polarized waves, a single carrier wave generator is provided in common for the OFDM transmit circuits, and a frequency converter in each OFDM transmit circuit multiplies a baseband signal by a common carrier wave, which is output from the carrier wave generator, to convert the baseband signal to a radio signal.

Claims

1. An OFDM transmitter apparatus for transmitting signals, which are output from first and second OFDM transmit circuits, utilizing two mutually orthogonal polarized waves, comprising:

a single carrier wave generator provided in common for the OFDM transmit circuits; and

a frequency converter provided in each OFDM transmit circuit for multiplying a baseband signal by a carrier wave, which is output from said carrier wave generator to convert the baseband signal to a radio signal.

2. An OFDM receiver apparatus having first and second OFDM receive circuits for demodulating respective ones of signals that have been transmitted utilizing two mutually orthogonal polarized waves, comprising:

a single carrier wave generator provided in common for the OFDM receive circuits; and

a frequency converter provided in each OFDM receive circuit for multiplying a radio signal by a carrier wave, which is output from said carrier wave generator to convert the radio signal to a baseband signal, and inputs said baseband signal to a demodulator provided in each OFDM receive circuit.

3. An OFDM receiver apparatus according to claim 2, wherein said OFDM receive circuits include:

a demodulator for performing demodulation onto said baseband signal;

an FFT arithmetic unit for applying FFT processing to a demodulated signal;

an error signal generator for generating an error signal based upon each carrier signal obtained by FFT; and

a cross-polarization interference canceller for correcting an output signal of said demodulator by generating a cross-polarization interference compensating signal using said error signal and a demodulated signal from the other OFDM receive circuit.

4. An OFDM receiver apparatus according to claim 2, wherein said OFDM receive circuits include:

a demodulator for performing demodulation onto said baseband signal;

an FFT arithmetic unit for applying FFT processing to a demodulated signal;

an error signal generator for generating an error signal based upon each carrier signal obtained by FFT; and

a cross-polarization interference canceller for correcting each carrier signal of said FFT by generating a cross-polarization interference compensating signal using said error signal and a demodulated signal from the other OFDM receive circuit.

5. On OFDM receiver apparatus having first and second OFDM receive circuits for demodulating respective ones of signals that have been transmitted utilizing two mutually orthogonal polarized waves, wherein said OFDM receive circuits include:

a frequency converter for multiplying a radio signal by a carrier wave to convert the radio signal to a baseband signal;

a demodulator for performing demodulation onto said baseband signal;

an FFT arithmetic unit for applying FFT processing to a demodulated signal;

an error signal generator for generating an error signal based upon each carrier signal obtained by FFT; and

a cross-polarization interference compensating canceller for correcting each carrier signal, that is output from said FFT, by generating a cross-polarization interference compensating signal using said error signal and a demodulated signal of the other OFDM receive circuit.