# US 2018/0027467 A1 · Method and apparatus for adjusting data transmission rate between vehicle and access point > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0027467 A1 - Document ID: US20180027467A1 - Status: Published application - Kind: A1 - Application number: 15/549,323 - Filed: 2016-02-04 - Published: 2018-01-25 - Earliest claimed: 2015-02-06 - Assignees: Dongguk University Industry-Academic Cooperation Foundation - Applicants: Dongguk University Industry-Academic Cooperation Foundation - Inventors: Seung Hoon HWANG; Seong Hyung LEE; Seong Hee LEE - Web page: https://patentgrep.com/patent/US20180027467A1 ## CPC - H04L 47/25: with rate being modified by the source upon detecting a change of network conditions - H04L 1/0003: {by switching between different modulation schemes} - H04W 28/0215: {based on user or device properties, e.g. MTC-capable devices (services for machine-to-machine communication [M2M] or machine type communication [MTC] H04W4/70; wireless resource selection or allocation plan definition based on terminal or device properties H04W72/51)} - H04W 28/0226: {based on location or mobility (handoff or reselection H04W36/00; mobile application services making use of the location of users or terminals H04W4/02)} - H04W 28/0236: {radio quality, e.g. interference, losses or delay} - H04W 36/18: for allowing seamless reselection, e.g. soft reselection - H04W 40/244: {using a network of reference devices, e.g. beaconing} - H04W 72/30: Resource management for broadcast services - H04W 72/542: using measured or perceived quality - H04L 67/12: specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks - H04L 2001/0093: {Point-to-multipoint} - H04W 36/304: {due to measured or perceived resources with higher communication quality} - H04W 36/324: {by mobility data, e.g. speed data} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Disclosed is a method of adjusting a data transmission rate between a vehicle and an access point (AP) as an embodiment of the present invention. The method according to an embodiment of the present invention may include receiving a signal broadcast from at least one AP near a vehicle, transmitting and/or receiving data to and/or from a predetermined AP at a first data transmission rate R0 on the basis of the received signal, receiving and storing signals broadcast from a plurality of APs near the vehicle in every predetermined period while the vehicle is moving, determining the number NT of APs having broadcast signals with strength greater than or equal to a threshold value among the signals received from the plurality of APs, comparing the number NT of APs to the number NT-1 of APs having broadcast signals with strength greater than or equal to the threshold value in a previous period, and determining a data transmission rate between the vehicle and the AP on the basis of a result of the comparison. ## Claims ### Claim 1 A method of adjusting a data transmission rate between a vehicle and an access point (AP), the method comprising: receiving a signal broadcast from at least one AP near the vehicle; transmitting and/or receiving data to and/or from a predetermined AP at a first data transmission rate R0 on the basis of the received signal; receiving and storing signals broadcast from a plurality of APs near the vehicle in every predetermined period while the vehicle is moving; determining the number NT of APs having broadcast signals with strength greater than or equal to a threshold value among the signals received from the plurality of APs; comparing the number NT of APs to the number NT-1 of APs having broadcast signals with strength greater than or equal to the threshold value in a previous period; and determining a data transmission rate between the vehicle and the AP on the basis of a result of the comparison. ### Claim 2 (depends on 1) The method of claim 1, wherein the signal broadcast from the AP includes a parameter indicating at least one of unique identification information (SSID), a cell ID, a state, transmission power, and a supported transmission rate of the AP. ### Claim 3 (depends on 1) The method of claim 1, wherein the predetermined AP is an AP having broadcast a signal with the greatest strength. ### Claim 4 (depends on 1) The method of claim 1, wherein the determining of a data transmission rate between the vehicle and the AP on the basis of a result of the comparison comprises: maintaining the data transmission rate between the vehicle and the AP at a current data transmission rate RT-1 when the number NT of APs having broadcast signals with strength greater than or equal to the threshold value in a current period is equal to the number NT-1 of APs having broadcast signals with strength greater than or equal to the threshold value in the previous period; decreasing the data transmission rate between the vehicle and the AP below RT-1 when NT-1 is less than NT; and increasing the data transmission rate between the vehicle and the AP above RT-1 when NT-1 is greater than NT. ### Claim 5 (depends on 1) The method of claim 1, further comprising changing a modulation scheme in order to adjust the data transmission rate between the vehicle and the AP to the determined data transmission rate, wherein the change of the modulation scheme includes changing a modulation level from a high level to a low level in order to decrease the data transmission rate or changing a modulation level from a low level to a high level in order to increase the data transmission rate. ### Claim 6 (depends on 1) The method of claim 1, wherein in a communication environment using a fixed modulation scheme, the data transmission rate itself between the vehicle and the AP is adjusted without the change of the modulation scheme. ### Claim 7 (depends on 6) The method of claim 6, wherein the adjustment of the data transmission rate itself between the vehicle and the AP is to decrease or increase the data transmission rate. ### Claim 8 (depends on 1) The method of claim 1, wherein: the data transmission rate between the vehicle and the AP is adjustable by a transmission period of data in a buffer being changed; and the data transmission rate is decreased by the transmission period of the data in the buffer being extended or is increased by the transmission period of the data in the buffer being shortened. ### Claim 9 (depends on 4) The method of claim 4, further comprising adjusting the data transmission rate to increase by the first data transmission rate R0 when the data transmission rate decreases to a minimum threshold value Rmin. ### Claim 10 (depends on 4) The method of claim 4, further comprising maintaining the data transmission rate at a maximum threshold value Rmax when the data transmission rate increases to the maximum threshold value Rmax. ### Claim 11 An apparatus for adjusting a data transmission rate between a vehicle and an access point (AP), the apparatus comprising: a communication unit configured to receive a signal broadcast from at least one AP near the vehicle and transmit and/or receive data to and/or from a predetermined AP at a first data transmission rate R0 on the basis of the received signal; a storage unit configured to receive signals broadcast from a plurality of APs near the vehicle through the communication unit in every predetermined period while the vehicle is moving and to store the received signals; an analysis unit configured to determine the number NT of APs having broadcast signals with strength greater than or equal to a threshold value among the signals received from the plurality of APs and to compare the number NT of APs to the number NT-1 of APs having broadcast signals with strength greater than or equal to the threshold value in a previous period; and a control unit configured to determine a data transmission rate between the vehicle and the AP on the basis of a result of the comparison. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the signal broadcast from the AP is a signal including a parameter indicating at least one of unique identification information (SSID), a cell ID, a state, transmission power, and a supported transmission rate of the AP. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein the predetermined AP is an AP having broadcast a signal with the greatest strength. ### Claim 14 (depends on 11) The apparatus of claim 11, wherein: the control unit maintains the data transmission rate between the vehicle and the AP at a current data transmission rate RT-1 when the number NT of APs having broadcast signals with strength greater than or equal to the threshold value in a current period is equal to the number NT-1 of APs having broadcast signals with strength greater than or equal to the threshold value in the previous period; the control unit decreases the data transmission rate between the vehicle and the AP below RT-1 when NT-1 is less than NT; and the control unit increases the data transmission rate between the vehicle and the AP above RT-1 when NT-1 is greater than NT. ### Claim 15 (depends on 11) The apparatus of claim 11, further comprising a changing unit configured to change a modulation scheme in order to adjust the data transmission rate between the vehicle and the AP to the determined data transmission rate, wherein the change of the modulation scheme includes changing a modulation level from a high level to a low level in order to decrease the data transmission rate or changing a modulation level from a low level to a high level in order to increase the data transmission rate. ### Claim 16 (depends on 11) The apparatus of claim 11, wherein in a communication environment using a fixed modulation scheme, the data transmission rate itself between the vehicle and the AP is adjusted by the control unit without the change of the modulation scheme. ### Claim 17 (depends on 16) The apparatus of claim 16, wherein the adjustment of the data transmission rate itself between the vehicle and the AP is to decrease or increase the data transmission rate. ### Claim 18 (depends on 11) The apparatus of claim 11, wherein: the data transmission rate between the vehicle and the AP is adjustable by a transmission period of data in a buffer connected with the communication unit being changed; and the data transmission rate is decreased by the transmission period of the data in the buffer being extended or is increased by the transmission period of the data in the buffer being shortened. ### Claim 19 (depends on 14) The apparatus of claim 14, wherein the control unit adjusts the data transmission rate to increase by the first data transmission rate R0 when the data transmission rate decreases to a minimum threshold value Rmin. ### Claim 20 (depends on 14) The apparatus of claim 14, wherein the control unit maintains the data transmission rate at a maximum threshold value Rmax when the data transmission rate increases to the maximum threshold value Rmax.