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US-12621100-B2 - Wireless communication method and wireless communication terminal using training signal

US12621100B2US 12621100 B2US12621100 B2US 12621100B2US-12621100-B2

Abstract

A wireless communication terminal is disclosed. The wireless communication terminal includes a transceiver configured to transmit/receive a wireless signal; and a processor configured to control an operation of the wireless communication terminal. The transceiver transmits a training signal to a base wireless communication terminal based on a sub-frequency band allocated from the base wireless communication terminal, and transmits data to the base wireless communication terminal through the sub-frequency band allocated from the base wireless communication terminal. The training signal is used, by the base wireless communication terminal, for receiving the data from the wireless communication terminal.

Inventors

  • Juhyung Son
  • Jinsam Kwak
  • Geonjung KO

Assignees

  • WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC.
  • SK TELECOM CO., LTD.

Dates

Publication Date
20260505
Application Date
20240726
Priority Date
20150420

Claims (6)

  1. 1 . A wireless communication terminal comprising: a transceiver; and a processor, wherein the processor is configured to, in uplink (UL) orthogonal frequency division multiple access (OFDMA) transmission: transmit, by using the transceiver, a first one or more fields through a frequency band to a base wireless communication terminal, wherein a preamble of a physical frame includes the first one or more fields to be transmitted in a unit of 20 MHz through the frequency band and a second one or more fields to be transmitted through a sub-frequency band of the frequency band, adjust a magnitude of a training signal corresponding to the sub-frequency band based on a number of subcarriers to be transmitted for the training signal corresponding to the sub-frequency band, wherein a plurality of training signals configured to be transmitted through an entire frequency band allocated for the UL OFDMA transmission include the training signal corresponding to the sub-frequency band and a training signal corresponding to a sub-frequency band which is not allocated to any wireless communication terminal, transmit, by using the transceiver, the second one or more fields through the sub-frequency band to the base wireless communication terminal, wherein the second one or more fields include a field including the training signal corresponding to the sub-frequency band and not including the training signal corresponding to the sub-frequency band which is not allocated to any wireless communication terminal, and transmit data through the sub-frequency band to the base wireless communication terminal, wherein the training signal corresponding to the sub-frequency band which is not allocated to any wireless communication terminal is not transmitted by any wireless communication terminal in the UL OFDMA transmission.
  2. 2 . The wireless communication terminal of claim 1 , wherein the processor is configured to adjust the magnitude of the training signal corresponding to the sub-frequency band further based on a number of subcarriers which are used for data transmission through the sub-frequency band.
  3. 3 . The wireless communication terminal of claim 2 , wherein the subcarriers which are used for the data transmission comprises a subcarrier for transmitting data and a subcarrier for transmitting a pilot signal.
  4. 4 . An operating method of a wireless communication terminal in uplink (UL) orthogonal frequency division multiple access (OFDMA) transmission, the method comprising: transmitting, to a base wireless communication terminal, a first one or more fields through a frequency band to a base wireless communication terminal, wherein a preamble of a physical frame includes the first one or more fields to be transmitted in a unit of 20 MHz through the frequency band and a second one or more fields to be transmitted through a sub-frequency band of the frequency band; adjusting a magnitude of a training signal corresponding to the sub-frequency band based on a number of subcarriers to be transmitted for the training signal corresponding to the sub-frequency band, wherein a plurality of training signals configured to be transmitted through an entire frequency band allocated for the UL OFDMA transmission include the training signal corresponding to the sub-frequency band and a training signal corresponding to a sub-frequency band which is not allocated to any wireless communication terminal; transmitting, to the base wireless communication terminal, the second one or more fields through the sub-frequency band, wherein the second one or more fields include a field including the training signal corresponding to the sub-frequency band and not including the training signal corresponding to the sub-frequency band which is not allocated to any wireless communication terminal; and transmitting, to the base wireless communication terminal, data through the sub-frequency band allocated from the base wireless communication terminal, wherein the training signal corresponding to the sub-frequency band which is not allocated to any wireless communication terminal is not transmitted by any wireless communication terminal in the UL OFDMA transmission.
  5. 5 . The method of claim 4 , wherein the adjusting the magnitude of the training signal corresponding to the sub-frequency band comprises adjusting the magnitude of the training signal corresponding to the sub-frequency band further based on a number of subcarriers which are used for data transmission through the sub-frequency band.
  6. 6 . The method of claim 5 , wherein the subcarriers which are used for the data transmission comprises a subcarrier for transmitting data and a subcarrier for transmitting a pilot signal.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 18/195,379 filed on May 10, 2023, which is a continuation of U.S. patent application Ser. No. 17/670,348 filed on Feb. 11, 2022, now issued as U.S. Pat. No. 11,722,277 dated Aug. 8, 2023, which is a continuation of U.S. patent application Ser. No. 16/844,817 filed on Apr. 9, 2020, now issued as U.S. Pat. No. 11,283,570 on Mar. 22, 2022, which is a continuation of U.S. patent application Ser. No. 15/719,547 filed on Sep. 29, 2017, issued as U.S. Pat. No. 10,666,405 on May 26, 2020, which is a continuation of International Patent Application No. PCT/KR2016/004131 filed on Apr. 20, 2016, which claims the priority to Korean Patent Application No. 10-2015-0055563 filed in the Korean Intellectual Property Office on Apr. 20, 2015, and Korean Patent Application No. 10-2015-0062726 filed in the Korean Intellectual Property Office on May 4, 2015, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD The present invention relates to a wireless communication method and a wireless communication terminal for setting a broadband link. Specifically, the present invention relates to a wireless communication method and a wireless communication terminal for delivering an efficient training signal for simultaneous communication with a plurality of terminals. BACKGROUND ART In recent years, with supply expansion of mobile apparatuses, a wireless communication technology that can provide a rapid wireless Internet service to the mobile apparatuses has been significantly spotlighted. The wireless communication technology allows mobile apparatuses including a smart phone, a smart pad, a laptop computer, a portable multimedia player, an embedded apparatus, and the like to wirelessly access the Internet in home or a company or a specific service providing area. One of most famous wireless communication technology is wireless LAN technology. Institute of Electrical and Electronics Engineers (IEEE) 802.11 has commercialized or developed various technological standards since an initial wireless LAN technology is supported using frequencies of 2.4 GHz. First, the IEEE 802.11b supports a communication speed of a maximum of 11 Mbps while using frequencies of a 2.4 GHz band. IEEE 802.11a which is commercialized after the IEEE 802.11b uses frequencies of not the 2.4 GHz band but a 5 GHz band to reduce an influence by interference as compared with the frequencies of the 2.4 GHz band which are significantly congested and improves the communication speed up to a maximum of 54 Mbps by using an Orthogonal Frequency Division Multiplexing (OFDM) technology. However, the IEEE 802.11a has a disadvantage in that a communication distance is shorter than the IEEE 802.11b. In addition, IEEE 802.11g uses the frequencies of the 2.4 GHz band similarly to the IEEE 802.11b to implement the communication speed of a maximum of 54 Mbps and satisfies backward compatibility to significantly come into the spotlight and further, is superior to the IEEE 802.11a in terms of the communication distance. Moreover, as a technology standard established to overcome a limitation of the communication speed which is pointed out as a weak point in a wireless LAN, IEEE 802.11n has been provided. The IEEE 802.11n aims at increasing the speed and reliability of a network and extending an operating distance of a wireless network. In more detail, the IEEE 802.11n supports a high throughput (HT) in which a data processing speed is a maximum of 540 Mbps or more and further, is based on a multiple inputs and multiple outputs (MIMO) technology in which multiple antennas are used at both sides of a transmitting unit and a receiving unit in order to minimize a transmission error and optimize a data speed. Further, the standard can use a coding scheme that transmits multiple copies which overlap with each other in order to increase data reliability. As the supply of the wireless LAN is activated and further, applications using the wireless LAN are diversified, the need for new wireless LAN systems for supporting a higher throughput (very high throughput (VHT)) than the data processing speed supported by the IEEE 802.11n has come into the spotlight. Among them, IEEE 802.11ac supports a wide bandwidth (80 to 160 MHz) in the 5 GHz frequencies. The IEEE 802.11ac standard is defined only in the 5 GHz band, but initial 11ac chipsets will support even operations in the 2.4 GHz band for the backward compatibility with the existing 2.4 GHz band products. Theoretically, according to the standard, wireless LAN speeds of multiple stations are enabled up to a minimum of 1 Gbps and a maximum single link speed is enabled up to a minimum of 500 Mbps. This is achieved by extending concepts of a wireless interface accepted by 802.11n, such as a wider wireless frequency bandwidth (a maximum of 160 MHz), more MIMO spatial streams (a maximum of 8), multi-user MIMO, and hig