# US 6,295,310 B1 · Mobile communication system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,295,310 B1 - Document ID: US6295310B1 - Status: Granted - Kind: B1 - Application number: 09/090,215 - Filed: 1998-06-04 - Granted: 2001-09-25 - Earliest claimed: 1997-06-12 - Assignees: Mitsubishi Denki Kabushiki Kaisha - Inventors: Takahisa Yamauchi; Akihiro Shibuya - Web page: https://patentgrep.com/patent/US6295310B1 ## CPC - H04B 1/713: using frequency hopping - H04B 2001/7154: {with means for preventing interference} - H04B: TRANSMISSION ## Abstract A mobile communication system which comprises a base station and a mobile station that communicates therewith while performing frequency hopping based on a predetermined hopping sequence. Based on the received power of a signal received from the base station at a first frequency in the hopping sequence, the mobile station switches the first frequency to a second one next thereto in the hopping sequence and keeps on communicating with the base station at the second frequency. ## Claims ### Claim 1 A mobile communication system which comprises a base station and a mobile station that communicates with said base station while performing frequency hopping based on a predetermined hopping sequence, wherein based on the received power of a signal received from said base station at a first frequency in said hopping sequence, said mobile station switches from said first frequency to a second frequency next to said first frequency in said hopping sequence and communicates with said base station at said second frequency, and said mobile station or said base station creates an original hopping sequence for communication between said mobile station and said base station by iteratively monitoring a plurality of candidate frequencies and selecting frequencies to be included in the original hopping sequence that satisfy at least one performance criterion. ### Claim 2 (depends on 1) A mobile communication system according to claim 1, wherein when said received power of said signal received from said base station at said first frequency in said hopping sequence is above a predetermined power level, said mobile station communicates with said base station at said first frequency, and when said received power is below said predetermined power level, said mobile station switches from said first frequency to said second frequency in said hopping sequence and communicates with said base station at said second frequency. ### Claim 3 (depends on 1) A mobile communication system according to claim 1, wherein, based on the received power of an interference received with said received signal of said first frequency, said first frequency in said hopping sequence is selectively switched to said second frequency for further communication between said base station and said mobile station. ### Claim 4 (depends on 3) A mobile communication system according to claim 3, wherein said base station and said mobile station communicate with each other at said first frequency when said received power of said interference received with said received signal of said first frequency is below a predetermined power level, and when said received power of said interference is above said predetermined power level, said first frequency in said hopping sequence is switched to said second frequency so that said base station and said mobile station continue to communicate with each other at said second frequency. ### Claim 5 (depends on 1) A mobile communication system according to claim 1, wherein said mobile station or base station selectively eliminates from said original hopping sequence one of a plurality of frequencies in said hopping sequence at which received signal power does not satisfy a predetermined requirement. ### Claim 6 (depends on 1) A mobile communication system according to claim 1, wherein said mobile station or base station detects the received power of a received signal at every frequency in said hopping sequence for each cycle during which said mobile station or base station performs frequency hopping to all the frequencies in said hopping sequence, then records in a recording part one of said frequencies at which the received power is maximum, and creates said original hopping sequence based on a plurality of frequencies recorded in said recording part. ### Claim 7 (depends on 6) A mobile communication system according to claim 6, wherein said mobile station or base station eliminates from said original hopping sequence one of a plurality of frequencies in said hopping sequence at which said received power of said received signal does not satisfy a predetermined requirement. ### Claim 8 (depends on 1) A mobile communication system according to claim 1, wherein said performance criterion relates to power level of a signal received on the candidate frequency. ### Claim 9 (depends on 1) A mobile communication system according to claim 1, wherein said mobile station or said base station iteratively selects the candidate frequency associated with a maximum power level of a received signal. ### Claim 10 (depends on 1) A mobile communication system according to claim 1, wherein said mobile station or said base station modifies said original hopping sequence by selectively eliminating frequencies that said mobile station or said base station determines to be inadequate. ### Claim 11 (depends on 10) A mobile communication system according to claim 10, wherein said mobile station or said base station eliminates a frequency from said original hopping sequence when a power level of a signal received on the frequency or an interference level on the frequency does not satisfy a threshold value. ### Claim 12 A mobile communication system which comprises a base station and a mobile station that communicates with said base station while performing frequency hopping based on a predetermined hopping sequence, wherein said mobile station outputs information based on the received power of a signal received from said base station at a first frequency in said hopping sequence and, based on said information, said base station switches from said first frequency to a second frequency next to said first frequency in said hopping sequence and communicates with said mobile station at said second frequency, and said mobile station or said base station creates an original hopping sequence for communication between said mobile station and said base station by iteratively monitoring a plurality of candidate frequencies and selecting frequencies to be included in the original hopping sequence that satisfy at least one performance criterion. ### Claim 13 A mobile communication system which comprises a mobile station and a base station that communicates with said mobile station while performing frequency hopping based on a predetermined hopping sequence, wherein based on the received power of a signal received from said mobile station at a first frequency in said hopping sequence, said base station switches from said first frequency to a second frequency next to said first frequency in said hopping sequence and communicates with said mobile station at said second frequency, and wherein said mobile station or said base station creates an original hopping sequence for communication between said mobile station and said base station by iteratively monitoring a plurality of candidate frequencies and selecting frequencies to be included in the original hopping sequence that satisfy at least one performance criterion. ### Claim 14 (depends on 13) A mobile communication system according to claim 13, wherein when said received power of said signal received from said mobile station at said first frequency in said hopping sequence is above a predetermined power level, said base station communicates with said mobile station at said first frequency, and when said received power is below said predetermined power level, said base station switches from said first frequency to said second frequency in said hopping sequence and communicates with said mobile station at said second frequency. ### Claim 15 (depends on 13) A mobile communication system according to claim 13, wherein, based on the received power of an interference received with said received signal of said first frequency, said first frequency in said hopping sequence is switched to a second frequency next to said first frequency for further communication between said base station and said mobile station. ### Claim 16 (depends on 15) A mobile communication system according to claim 15, wherein said base station and said mobile station communicate with each other at said first frequency when said received power of said interference received with said received signal of said first frequency is below a predetermined power level, and when said received power of said interference is above said predetermined power level, said first frequency in said hopping sequence is switched to said second frequency so that said base station and said mobile station continue to communicate with each other at said second frequency. ### Claim 17 (depends on 13) A mobile communication system according to claim 13, wherein said mobile or base station eliminates from said original hopping sequence one of a plurality of frequencies in said hopping sequence at which received signal power does not satisfy a predetermined requirement. ### Claim 18 (depends on 10) A mobile communication system according to claim 10, wherein said mobile station or base station detects the received power of a received signal at every frequency in said hopping sequence for each cycle during which said mobile station or base station performs frequency hopping to all the frequencies in said hopping sequence, then records in a recording part one of said frequencies at which the received power is maximum, and creates said original hopping sequence based on plural frequencies recorded in said recording part. ### Claim 19 (depends on 16) A mobile communication system according to claim 16, wherein said mobile station or base station eliminates from said original hopping sequence one of a plurality of frequencies in said hopping sequence at which said received power of said received signal does not satisfy a predetermined requirement. ### Claim 20 (depends on 13) A mobile communication system according to claim 13, wherein said performance criterion relates to power level of a signal received on the candidate frequency. ### Claim 21 (depends on 20) A mobile communication system according to claim 20, wherein said mobile station or said base station iteratively selects the candidate frequency associated with a maximum power level of a received signal. ### Claim 22 (depends on 13) A mobile communication system according to claim 13, wherein said mobile station or said base station modifies said original hopping sequence by selectively eliminating frequencies that said mobile station or said base station determines to be inadequate. ### Claim 23 (depends on 22) A mobile communication system according to claim 22, wherein said mobile station or said base station eliminates a frequency from said original hopping sequence when a power level of a signal received on the frequency or an interference level for the frequency does not satisfy a threshold value. ### Claim 24 A mobile communication system which comprises a mobile station and a base station that communicates with said mobile station while performing frequency hopping based on a predetermined hopping sequence, wherein said base station outputs information based on the received power of a signal received from said mobile station at a first frequency in said hopping sequence and, based on said information, said mobile station switches said first frequency to a second frequency next to said first frequency in said hopping sequence and communicates with said base station at said second frequency, and said mobile station or said base station creates an original hopping sequence for communication between said mobile station and said base station by iteratively monitoring a plurality of candidate frequencies and selecting frequencies to be included in the original hopping sequence that satisfy at least one performance criterion. ### Claim 25 A mobile communication system which comprises a base station and a mobile station that communicates with said base station while performing frequency hopping based on a predetermined hopping sequence, wherein based on the received power of an interference received with a received signal from said base station at a first frequency in said hopping sequence, said mobile station switches from said first frequency to a second frequency next to said first frequency in said hopping sequence and communicates with said base station at said second frequency, and said mobile station or said base station creates an original hopping sequence for communication between said mobile station and said base station by iteratively monitoring a plurality of candidate frequencies and selecting frequencies to be included in the original hopping sequence that satisfy at least one performance criterion. ### Claim 26 (depends on 25) A mobile communication system according to claim 25, wherein when said received power of said interference received with said receive signal from said base station at said first frequency in said hopping sequence is below a predetermined power level, said mobile station communicates with said base station at said first frequency, and when said received power of said interference is above said predetermined power level, said mobile station switches from said first frequency to said second frequency in said hopping sequence and communicates with said base station at said second frequency. ### Claim 27 (depends on 25) A mobile communication system according to claim 25 wherein said mobile station or base station eliminates from said original hopping sequence one of a plurality of frequencies in said hopping sequence at which said received power of said interference does not satisfy a predetermined requirement. ### Claim 28 (depends on 25) A mobile communication system according to claim 25, wherein said mobile station or base station detects the received power of interference at every frequency in said hopping sequence for each cycle during which said mobile station or base station performs frequency hopping to all the frequencies in said hopping sequence, then records in a recording part one of said frequencies at which the received power is maximum, and creates said original hopping sequence based on a plurality of frequencies recorded in said recording part. ### Claim 29 (depends on 28) A mobile communication system according to claim 28, wherein said mobile station or base station eliminates from said original hopping sequence one of a plurality of frequencies in said hopping sequence at which said received power of said interference does not satisfy a predetermined requirement. ### Claim 30 (depends on 25) A mobile communication system according to claim 25, wherein said performance criterion relates to power level of a signal received on the candidate frequency. ### Claim 31 (depends on 30) A mobile communication system according to claim 30, wherein said mobile station or said base station iteratively selects the candidate frequency associated with a maximum power level of a received signal. ### Claim 32 (depends on 25) A mobile communication system according to claim 25, wherein said mobile station or said base station modifies said original hopping sequence by selectively eliminating frequencies that said mobile station or said base station determines to be inadequate. ### Claim 33 (depends on 32) A mobile communication system according to claim 32, wherein said mobile station or said base station eliminates a frequency from said original hopping sequence when a power level of a signal received on the frequency or an interference level for the frequency does not satisfy a threshold value. ### Claim 34 A mobile communication system which comprises a base station and a mobile station that communicates with said base station while performing frequency hopping based on a predetermined hopping sequence, wherein said mobile station outputs information based on the received power of an interference received with a signal received from said base station at a first frequency in said hopping sequence and, based on said information, said base station switches from said first frequency to a second frequency next to said first frequency in said hopping sequence and communicates with said mobile station at said second frequency, and said mobile station or said base station creates an original hopping sequence for communication between said mobile station and said base station by iteratively monitoring a plurality of candidate frequencies and selecting frequencies to be included in the original hopping sequence that satisfy at least one performance criterion. ### Claim 35 A mobile communication system which comprises a mobile station and a base station that communicates with said mobile station while performing frequency hopping based on a predetermined hopping sequence, wherein based on the received power of an interference received with a received signal from said mobile station at a first frequency in said hopping sequence, said base station switches from said first frequency to a second frequency next to said first frequency in said hopping sequence and communicates with said mobile station at said second frequency, and said mobile station or said base station creates an original hopping sequence for communication between said mobile station and said base station by iteratively monitoring a plurality of candidate frequencies and selecting frequencies to be included in the original hopping sequence that satisfy at least one performance criterion. ### Claim 36 (depends on 35) A mobile communication system according to claim 35, wherein when said received power of said interference received with said received signal from said mobile station at said first frequency in said hopping sequence is below a predetermined power level, said base station communicates with said mobile station at said first frequency, and when said received power of said interference is above said predetermined power level, said base station switches from said first frequency to said second frequency in said hopping sequence and communicates with said mobile station at said second frequency. ### Claim 37 (depends on 35) A mobile communication system according to claim 35, wherein said mobile station or base station eliminates from said original hopping sequence one of a plurality of frequencies in said hopping sequence at which said received power of said interference does not satisfy a predetermined requirement. ### Claim 38 (depends on 35) A mobile communication system according to claim 35, wherein said mobile station or base station detects the received power of interference at every frequency in said hopping sequence for each cycle during which said mobile station or base station performs frequency hopping to all the frequencies in said hopping sequence, then records in a recording part one of said frequencies at which the received power is maximum, and creates said original hopping sequence based on a plurality of frequencies recorded in said recording part. ### Claim 39 (depends on 38) A mobile communication system according to claim 38, wherein said mobile station or base station eliminates from said original hopping sequence one of a plurality of frequencies in said hopping sequence at which said received power of said interference does not satisfy a predetermined requirement. ### Claim 40 (depends on 35) A mobile communication system according to claim 35, wherein said performance criterion relates to power level of a signal received on the candidate frequency. ### Claim 41 (depends on 40) A mobile communication system according to claim 40, wherein said mobile station or said base station iteratively selects the candidate frequency associated with a maximum power level of a received signal. ### Claim 42 (depends on 35) A mobile communication system according to claim 35, wherein said mobile station or said base station modifies said original hopping sequence by selectively eliminating frequencies that said mobile station or said base station determines to be inadequate. ### Claim 43 (depends on 42) A mobile communication system according to claim 42, wherein said mobile station or said base station eliminates a frequency from said original hopping sequence when a power level of a signal received on the frequency or an interference level on the frequency does not satisfy a threshold value. ### Claim 44 A mobile communication system which comprises a mobile station and a base station that communicates with said mobile station while performing frequency hopping based on a predetermined hopping sequence, wherein said base station outputs information based on the received power of an interference received with a signal received from said mobile station at a first frequency in said hopping sequence and, based on said information, said mobile station switches from said first frequency to a second frequency next to said first frequency in said hopping sequence and communicates with said base station at said second frequency, and said mobile station or said base station creates an original hopping sequence for communication between said mobile station and said base station by iteratively monitoring a plurality of candidate frequencies and selecting frequencies to be included in the original hopping sequence that satisfy at least one performance criterion. ### Claim 45 A mobile communication system which comprises a base station, a first mobile station that communicates with said base station while performing frequency hopping based on a first hopping sequence, and a second mobile station that communicates with said base station while performing frequency hopping based on a second hopping sequence, wherein when said first mobile station, which communicates with said base station at a first frequency in said first hopping sequence, continues to communicate with said base station at said first frequency based on the received power of a signal received from said base station at said first frequency, said second mobile station communicates with said base station while performing frequency hopping based on said second hopping sequence composed of a plurality of frequencies except said first frequency, and said first mobile station or said base station creates an original hopping sequence for communication between said first mobile station and said base station by iteratively monitoring a plurality of candidate frequencies and selecting frequencies to be included in the original hopping sequence that satisfy at least one performance criterion. ### Claim 46 (depends on 45) A mobile communication system according to claim 45, wherein said first mobile station communicates with said base station at said first frequency in said first hopping sequence, and when said received power of said signal received from said base station at said first frequency is above a predetermined power level, said first mobile station continues to communicate with said base station at said first frequency. ### Claim 47 (depends on 33) A mobile communication system according to claim 33, wherein said first mobile station communicates with said base station at said first frequency in said first hopping sequence and when said received power of said signal received from said base station at said first frequency is above a predetermined power level, said first mobile station continues to communicate with said base station at said first frequency, and wherein said second mobile station communicates with said base station at a second frequency in said second hopping sequence and when the received power of a signal received from said base station at said second frequency is below a predetermined power level, said second mobile station communicates with said base station while performing frequency hopping based on said second hopping sequence composed of a plurality of frequencies except said first frequency.