Orthogonal frequency division multiplexing (OFDM) receiving device for forming beam with uneven width by channel property, communication device using the same, and method thereof

• US 20020106042A1
• Filed: 11/01/2001
• Published: 08/08/2002
• Est. Priority Date: 02/08/2001
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Park, Hyun-Cheol, Kim, Dong-Kyu, Kim, Ju-Yon, Ko, Hak-Lim, Yu, Bong-Wee, Park, Jun-Hyun
• Granted Patent: US 7,327,797 B2
• Time in Patent Office: Days
• US Class Current: 375/347
• CPC Class Codes: H04B 7/0408 using two or more beams, i.e. beam diversity
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/086 using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming

Abstract

An OFDM receiving device for adjusting a beam formation azimuth through a plurality of antennas, a communication device using the same, and a method thereof. The OFDM communication device having a plurality of individually-aligned antennas includes a receiving signal generating unit for decoding and restoring OFDM signals from the plurality of antennas, a beam coefficient calculating unit for calculating channel property information inclusive of a signal to noise rate, from the signal received from the receiving signal generating unit, and calculating a beam coefficient of an antenna, for forming a beam in a configuration that optimizes reception sensitivity, from the channel property information, a receiving beam processing unit for outputting the signals from the antennas to the receiving signal generating unit, and controlling the corresponding antenna to form a beam in a configuration corresponding to the beam coefficient received from the beam coefficient calculating unit, a transmitting signal generating unit for modulating a transmission-intended signal into a transmitting signal, and a transmission beam processing unit for controlling the antenna according to the beam coefficient from the beam coefficient calculating unit in order to transmit the transmitting signal through the antenna.

Claims

1. An Orthogonal Frequency Division Multimplexing (OFDM) receiving device for forming a beam with uneven width according to a channel property, comprising:

a receiving signal generating unit for decoding and restoring OFDM signals from a plurality of antennas;

a beam coefficient calculating unit for calculating channel property information inclusive of a signal to noise rate, from signals received from the receiving signal generating unit, and calculating a beam coefficient for one of the plurality of antennas for forming a beam in a configuration that optimizes reception sensitivity from the channel property information; and

a receiving beam processing unit for outputting the OFDM signals from the plurality of antennas to the receiving signal generating unit, and controlling a corresponding one of the plurality of antennas to form a beam in a configuration corresponding to the beam coefficient received from the beam coefficient calculating unit.

2. The device according to claim 1, wherein the receiving signal generating unit is connected to a host for processing the decoded signals.

3. The device according to claim 2, wherein the receiving signal generating unit comprises:

a high frequency amplifying unit for high-frequency amplifying the signals output from the receiving beam processing unit and received from the plurality of antennas;

a low frequency amplifying unit for detecting original signals from the high-frequency amplified signals, and low-frequency amplifying the detected signals;

an analog-digital converting unit for converting the low-frequency amplified analog signals into digital signals; and

a receiving signal decoding unit for selecting a signal having high reception sensitivity to the original signals from the digital signals, and outputting the selected signal to the host.

4. The device according to claim 3, wherein the signal to noise rate is obtained by calculating an original signal to noise rate of respective OFDM signals based on the low-frequency amplified signal from the low frequency amplifying unit.

5. The device according to claim 4, wherein the channel property information comprises bit to error rates of the respective OFDM signals showing an error bit number of a whole bit number of the digital signals from the analog-digital converting unit.

6. The device according to claim 5, wherein the channel property information further comprises beam load information of each of the plurality of antennas, showing an amount of the received information of beams formed on the plurality of antennas through the decoded signals of the received OFDM signals.

7. The device according to claim 6, wherein the channel property information further comprises receiving power values of the respective OFDM signals calculated by measuring power of the OFDM signals received from the high frequency amplifying unit based on their amplitudes.

8. The device according to claim 7, wherein the beam coefficient calculating unit comprises:

a receiving power measuring unit for measuring a receiving power corresponding to amplitudes of the OFDM signals from the high frequency amplifying unit;

a beam load measuring unit for measuring signal reception density according to reception of the plurality of antennas through the decoded signals of the OFDM signals received from the receiving signal generating unit;

a receiving distortion calculating unit for calculating a distortion noise rate from the signals received from the low frequency amplifying unit, and a distortion signal rate from the bit signals received from the analog-digital converting unit;

an optimal beam detecting unit for detecting an optimal beam parameter for receiving the OFDM signals from the receiving power values, beam load information, and receiving distortion values; and

a receiving beam coefficient setup unit for calculating a beam coefficient for forming the beam corresponding to the optimal beam parameter on one of the plurality of antennas.

9. The device according to claim 8, wherein the receiving distortion calculating unit comprises:

a signal to noise rate calculating unit for calculating a signal to noise rate accompanying the signal power from the amplitudes of the low-frequency amplified signals from the low frequency amplifying unit; and

a bit to error rate calculating unit for detecting an error bit number from the whole bit number of the digital signals received from the analog-digital converting unit, and calculating a bit to error rate for the whole bit number.

10. The device according to claim 9, wherein the receiving beam coefficient setup unit comprises:

a beam coefficient selecting unit for calculating a beam coefficient corresponding to the optimal beam parameter from the optimal beam detecting unit to form a beam corresponding to the optimal beam parameter; and

a coefficient switching unit for switching the beam coefficient to the receiving beam processing unit according to a switching control signal.

11. The device according to claim 10, wherein the receiving beam coefficient setup unit further comprises a lookup table for storing beam coefficient information for forming a width of the beam corresponding to the optimal beam parameter.

12. The device according to claim 11, wherein the receiving beam coefficient setup unit further comprises a selected beam coefficient storing unit for storing the beam coefficient selected by the beam coefficient selecting unit.

14. The device according to claim 13, further comprising:

a beam coefficient control unit for controlling the beam coefficient calculated by the beam coefficient calculating unit to be output to the receiving beam processing unit or the transmitting beam processing unit, wherein the receiving signal generating unit and the transmitting signal generating unit are connected to a host for processing an external decoded signal or transmitting the transmission-intended signal.

15. The device according to claim 14, further comprising a signal switching unit for switching a signal to the receiving beam processing unit according to a signal switching signal from the host when the signal is input through said one of the plurality of antennas, and for switching the transmission-intended signal to said one of the antennas according to the signal switching signal from the host when the signal is output to said one of the plurality of antennas.

17. The method according to claim 16, wherein the channel property comprises at least one of the signal to noise rates, bit to error rates, beam load information, and receiving power values of each of the plurality of received signals.

18. The method according to claim 17, wherein the beam coefficient calculating process comprises the steps of:

measuring a receiving power from a high-frequency amplified signal of said at least one of the plurality of signals, calculating a signal to noise rate from a low-frequency amplified signal thereof, and calculating a bit to error rate accompanying a whole bit number of a digital signal;

detecting an optimal beam parameter of said at least one of the plurality of signals having a high receiving power, low signal to noise rate, and low bit to error rate, from the measured receiving power, signal to noise rate, and bit to error rate; and

calculating a beam coefficient corresponding to the optimal beam parameter.

13. An Orthogonal Frequency Division Multimplexing (OFDM) communication device for forming a beam with uneven width according to a channel property, comprising:

a receiving signal generating unit for decoding and restoring OFDM signals from a plurality of antennas;

a beam coefficient calculating unit for calculating channel property information inclusive of a signal to noise rate, from signals received from the receiving signal generating unit, and calculating a beam coefficient for one of the plurality of antennas for forming a beam in a configuration that optimizes reception sensitivity, from the channel property information;

a receiving beam processing unit for outputting the OFDM signals from the plurality of antennas to the receiving signal generating unit, and controlling a corresponding one of the plurality of antennas to form a beam in a configuration corresponding to the beam coefficient calculated by the beam coefficient calculating unit;

a transmitting signal generating unit for modulating a transmission-intended signal into a transmitting signal; and

a transmission beam processing unit for controlling said one of the plurality of antennas according to the beam coefficient calculated by the beam coefficient calculating unit in order to transmit the transmitting signal through said one of the plurality of antennas.

16. An Orthogonal Frequency Division Multimplexing (OFDM) communication method for forming a beam with uneven width according to a channel property, comprising the steps of:

determining whether at least one of a plurality of signals is received from at least one of a plurality of antennas;

calculating channel property information from said at least one of the plurality of signals, and calculating a beam coefficient corresponding to an antenna beam configuration for improving communication performance, from the channel property information, when said at least one of the plurality of signals is received from at least one of the plurality of antennas; and

adjusting a beam formation azimuth of said at least one of the plurality of antennas to form a beam corresponding to the calculated beam coefficient.