Transmission/reception apparatus and method for frequency domain signal processing in a smart antenna system
First Claim
1. A signal receiving apparatus of a base station in a smart antenna system which uses an Orthogonal Frequency Division Multiplexing (OFDM) communication scheme, the signal receiving apparatus comprising:
- a plurality of Fast Fourier Transform (FFT) units for performing FFT according to a predetermined FFT window on a plurality of incoming signals received through a plurality of antennas an FFT window detector for detecting a boundary of an OFDM symbol and setting the FFT window with a margin as large as a predetermined FFT window offset with reference to the detected symbol boundary;
a calibration signal generator for outputting an FFT window calibration signal based on the FFT window offset; and
a plurality of first multipliers for multiplying each of the incoming signals output from the FFT units by the FFT window calibration signal.
2 Assignments
0 Petitions
Accused Products
Abstract
An apparatus and a method can improve the performance of a smart antenna system for signal processing in the frequency domain. The method includes: performing Fast Fourier Transform (FFT) on a plurality of incoming signals received through antennas according to a predetermined FFT window; detecting a boundary of an OFDM symbol and setting the FFT window with a margin as large as a predetermined FFT window offset with reference to the detected symbol boundary; receiving the FFT window offset and generating an FFT window calibration signal; and multiplying the FFT-processed incoming signals by the FFT window calibration signal. The method can improve the reception performance of a base station by compensating for the multi-path channel by using an RX FEQ coefficient obtained by a receiver of a terminal as an FEQ weight of a transmitter of the terminal. Further, the method can generate a uniform non-directional beam by generating a variable omni-directional beam pattern in a smart antenna system.
-
Citations
34 Claims
-
1. A signal receiving apparatus of a base station in a smart antenna system which uses an Orthogonal Frequency Division Multiplexing (OFDM) communication scheme, the signal receiving apparatus comprising:
-
a plurality of Fast Fourier Transform (FFT) units for performing FFT according to a predetermined FFT window on a plurality of incoming signals received through a plurality of antennas an FFT window detector for detecting a boundary of an OFDM symbol and setting the FFT window with a margin as large as a predetermined FFT window offset with reference to the detected symbol boundary; a calibration signal generator for outputting an FFT window calibration signal based on the FFT window offset; and a plurality of first multipliers for multiplying each of the incoming signals output from the FFT units by the FFT window calibration signal. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A signal receiving apparatus of a base station in a smart antenna system which uses an Orthogonal Frequency Division Multiplexing (OFDM) communication scheme, the signal receiving apparatus comprising:
-
a plurality of Fast Fourier Transform (FFT) units for performing FFT according to a predetermined FFT window on a plurality of incoming signals received through a plurality of antennas; an FFT window detector for detecting a boundary of an OFDM symbol and setting the FFT window with a margin as large as a predetermined FFT window offset with reference to the detected OFDM symbol boundary; a calibration signal generator for outputting an FFT window calibration signal based on the FFT window offset; a plurality of first multipliers for multiplying a predetermined reference signal for frequency domain equalizer (FEQ) coefficient estimation by the FFT window calibration signal; and a reception (RX) beam forming weight calculator for calculating an RX beam forming weight for each of antenna paths by using the incoming signals output from the FFT units and signals output from the first multipliers. - View Dependent Claims (9, 10, 11, 12, 13)
-
-
14. A signal receiving apparatus of a mobile terminal in a smart antenna system which uses an Orthogonal Frequency Division Multiplexing (OFDM) communication scheme, the signal receiving apparatus comprising:
-
a Fast Fourier Transform (FFT) unit for performing FFT according to a predetermined FFT window on an incoming signal received through an antenna; an FFT window detector for detecting a boundary of an OFDM symbol and setting the FFT window with a margin as large as a predetermined FFT window offset with reference to the detected OFDM symbol boundary; a calibration signal generator for outputting an FFT window calibration signal based on the FFT window offset; a first multiplier for multiplying the incoming signal output from the FFT unit by the FFT window calibration signal; and a frequency domain equalizer (FEQ) estimator for estimating FEQ coefficients by using a signal output from the first multiplier and a predetermined reference signal. - View Dependent Claims (15)
-
-
16. A signal receiving apparatus of a mobile terminal in a smart antenna system which uses an Orthogonal Frequency Division Multiplexing (OFDM) communication scheme, the signal receiving apparatus comprising:
-
a Fast Fourier Transform (FFT) unit for performing FFT according to a predetermined FFT window on incoming signal received through an antenna; an FFT window detector for detecting a boundary of an OFDM symbol and setting the FFT window with a margin as large as a predetermined FFT window offset with reference to the detected OFDM symbol boundary; a calibration signal generator for outputting an FFT window calibration signal based on the FFT window offset; a first multiplier for multiplying a predetermined reference signal for frequency domain equalizer (FEQ) coefficient estimation by the FFT window calibration signal; and a FEQ estimator for estimating FEQ coefficients by using a signal output from the FFT unit and the compensated reference signal transferred from the first multiplier. - View Dependent Claims (17)
-
-
18. A signal transmitting apparatus of a base station in a smart antenna system which uses an Orthogonal Frequency Division Multiplexing (OFDM) communication scheme, the signal transmitting apparatus comprising:
-
a mapper for mapping outgoing signals according to a predetermined modulation scheme for transmission to a mobile terminal; a multiplexer for selectively outputting transmission (TX) beam forming weights for forming a directional beam pattern or TX omni weights for forming an omni-directional beam pattern; a plurality of multiplier for multiplying the outgoing signals by weight signals output from the multiplexer; and a controller for outputting the TX omni weights time-variably and generating the omni-directional beam pattern when the omni-directional beam pattern is selected.
-
-
19. A signal receiving method of a base station in a smart antenna system which uses an Orthogonal Frequency Division Multiplexing (OFDM) communication scheme, the signal receiving method comprising the steps of:
-
(a) performing Fast Fourier Transform (FFT) according to a predetermined FFT window on a plurality of incoming signals received through a plurality of antennas; (b) detecting a boundary of an OFDM symbol and setting the FFT window with a margin as large as a predetermined FFT window offset with reference to the detected OFDM symbol boundary; (c) generating an FFT window calibration signal based on the FFT window offset; and (d) multiplying each of the FFT-processed incoming signals by the FFT window calibration signal. - View Dependent Claims (20, 21, 22, 23, 24, 25)
-
-
26. A signal receiving method of a base station in a smart antenna system which uses an Orthogonal Frequency Division Multiplexing (OFDM) communication scheme, the signal receiving method comprising:
-
(a) performing Fast Fourier Transform (FFT) according to a predetermined FFT window on a plurality of incoming signals received through a plurality of antennas; (b) detecting a boundary of an OFDM symbol and setting the FFT window with a margin as large as a predetermined FFT window offset with reference to the detected OFDM symbol boundary; (c) generating an FFT window calibration signal based on the FFT window offset; (d) multiplying a predetermined reference signal for frequency domain equalizer (FEQ) coefficient estimation by the FFT window calibration signal; and (e) calculating an RX beam forming weight for each of the antenna paths by using the FFT-processed incoming signals and a signal generated by the step (d). - View Dependent Claims (27, 28, 29, 30, 31)
-
-
32. A signal transmission/reception method of a mobile terminal in a smart antenna system which uses an Orthogonal Frequency Division Multiplexing (OFDM) communication scheme, the mobile terminal comprising a transmitter and a receiver, wherein the signal transmission/reception method comprises the steps of:
-
(a) performing, by the receiver, Fast Fourier Transform (FFT) on an incoming signal received through an antenna according to a predetermined FFT window; (b) detecting, by the receiver, a boundary of an OFDM symbol and setting the FFT window with a margin as large as a predetermined FFT window offset with reference to the detected OFDM symbol boundary; (c) generating, by the receiver, an FFT window calibration signal based on the FFT window offset; (d) multiplying, by the receiver, the FFT-processed incoming signal by the FFT window calibration signal; (e) estimating, by the receiver, frequency domain equalizer (FEQ) coefficients by using signal generated by the step (d) and a predetermined reference signal; and (f) multiplying, by the transmitter, an input outgoing signal by the FEQ coefficients as weights.
-
-
33. A signal transmission/reception method of a mobile terminal in a smart antenna system which uses an Orthogonal Frequency Division Multiplexing (OFDM) communication scheme, the mobile terminal comprising a transmitter and a receiver, wherein the signal transmission method/reception comprises the steps of:
-
(a) performing, by the receiver, Fast Fourier Transform (FFT) according to a predetermined FFT window on incoming signal received through antenna; (b) detecting, by the receiver, a boundary of an OFDM symbol and setting the FFT window with a margin as large as a predetermined FFT window offset with reference to the detected OFDM symbol boundary; (c) receiving the FFT window offset and generating an FFT window calibration signal based on the FFT window offset; (d) multiplying, by the receiver, a predetermined reference signal for frequency domain equalizer (FEQ) coefficient estimation by the FFT window calibration signal; (e) estimating, by the receiver, frequency domain equalizer (FEQ) coefficients by using the FFT-processed incoming signal and the compensated reference signal; and (f) multiplying, by the transmitter, an input outgoing signal by the FEQ coefficients as weights.
-
-
34. A signal transmission method of a base station in a smart antenna system which uses an Orthogonal Frequency Division Multiplexing (OFDM) communication scheme, the signal transmission method comprising the steps of:
-
mapping outgoing signals according to a predetermined modulation scheme for transmission to a mobile terminal; selectively outputting transmission (TX) beam forming weights for forming a directional beam pattern or TX omni weights for forming an omni-directional beam pattern; and multiplying the outgoing signals by the TX omni weights time-variably output and generating the omni-directional beam pattern when the omni-directional beam pattern is selected.
-
Specification