Method and apparatus for transmitting data packets over voice channel

• US 6,044,266 A
• Filed: 08/22/1997
• Issued: 03/28/2000
• Est. Priority Date: 08/27/1996
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Kato, Hidenori
• Primary Examiner(s): Hunter, Daniel S.
• Assistant Examiner(s): Woldetatios, Yemane
• Application Number:
  US08/916,268
• Time in Patent Office: 949 Days
• Field of Search: 455/422, 455/432, 455/466, 455/456, 455/450, 455/434, 455/436, 455/438, 455/419, 455/445, 455/464, 370/433, 370/435, 370/465, 370/528
• US Class Current: 455/422.1
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal

Abstract

A communication system includes a first station in voice communication with a base station and a second station in data communication with the base station. The second station monitors the voice communication and identifies predetermined periods (e.g., preferably silent periods) of the voice communication. The second station transmits data packets during the predetermined periods.

Claims

1. A system for acquiring a channel in radio packet data communication for use with a base station and a mobile station, in communication with said base station, for transmitting a voice burst, comprising:

a receiver for receiving said voice burst and measuring a receiving level thereof;

a ranking section for ranking a receiving state of said receiver based on receiving levels of radio waves transmitted from said mobile station; and

a channel monitoring and control section for selecting a channel with a predetermined receiving state based on an output from said ranking section, and for monitoring the receiving state of the channel,

wherein, for packet data communication, said mobile station selectively uses an idle channel and other channels engaged for voice communication by other mobile stations such that when said mobile station is determined not to be transmitting a voice burst on the channel, said channel is interrupted and packet data is transmitted thereover, and

wherein, when a voice burst is transmitted on said channel during transmission of said packet data, the transmission of packet data is suspended, and a second mobile station not transmitting a voice burst is identified, thereby to obtain said idle channel for said radio packet data communication.

2. The system according to claim 1, wherein, when said idle channel selected for the packet data transmission by the channel monitoring and control section is used for voice communication before termination of packet data transmission, said channel monitoring and controlling section suspends the transmission of packet data, monitors for a burst which indicates termination of the voice burst, and interrupts a channel not transmitting a voice burst.

3. The system according to claim 1, further comprising a switching circuit coupled to said channel monitoring and control section.

4. The system according to claim 3, wherein, when said channel monitoring and control section receives from said ranking section information indicating termination of the voice burst as a silent state, the channel monitoring and control section determines that the channel is usable, and activates said switching circuit to transmit packet data.

5. The system according to claim 4, wherein, when said channel monitoring and control section receives from said ranking section information indicating starting of the voice burst as a taking state, said channel monitoring and control section confirms, based on said information, a state where no burst is transmitted on the channel, determines that said channel cannot be used, and controls the packet data transmission to de-activate said switching circuit.

6. The system according to claim 2, further comprising a switching circuit coupled to said channel monitoring and control section.

7. The system according to claim 6, wherein, when said channel monitoring and control section receives from said ranking section information indicating termination of the voice burst as a silent state, the channel monitoring and control section determines that the channel is usable, and activates said switching circuit to transmit packet data.

8. The system according to claim 7, wherein, when said channel monitoring and control section receives from said ranking section information indicating starting of the voice burst as a talking state, said channel monitoring and control section confirms, based on said information, a state where no burst is transmitted on the channel, determines that said channel cannot be used, and controls the packet data transmission to de-activate said switching circuit.

9. The system according to claim 1, wherein said mobile station monitors channels used by said other mobile stations and selects one of a predetermined good quality channel for said packet data communication, and

wherein said channel monitoring and control section utilizes a VOX control to detect a silent period in an engaged channel for one of transmitting packet data and inserting packet data into said silent period.

10. The system according to claim 1, wherein said system is selectively employed in any one of said base station and said mobile station.

11. A system for acquiring a channel in radio packet data communication for use with a base station and a mobile station, in communication with said base station, for transmitting a voice burst, comprising:

a receiver for receiving said voice burst and measuring a receiving level thereof;

a ranking section for ranking a receiving state of said receiver based on receiving levels of radio waves transmitted from said mobile station; and

a channel monitoring and control section for selecting a channel with a predetermined receiving state based on an output from said ranking section, and for monitoring the receiving state of the channel,

wherein, when said mobile station is determined not to be transmitting a voice burst on the channel, said channel is interrupted and packet data is transmitted thereover, and

wherein, when a voice burst is transmitted on said channel during transmission of said packet data, the transmission of packet data is suspended, and a second mobile station not transmitting a voice burst is identified, thereby to obtain an idle channel for radio packet data communication,

wherein said ranking section comprises;

a power level measuring section for measuring a power level of said receiving levels of radio waves transmitted from said mobile station;

a power level comparing section for comparing said power level with a predetermined level;

a memory for storing levels of channels determined to have a level above said predetermined level and a respective channel number; and

a level selection section for selecting a channel having a highest level of said channels determined to have a level above said predetermined level, said level selection section providing an output to said channel monitoring and control section.

12. The system according to claim 11, wherein said channel monitoring and control section comprises:

a postamble monitoring/supervising section for receiving an output from said level selection section and for monitoring postambles of a selected channel, such that packet data is transmitted when a postamble has been received by said channel monitoring and control section; and

a collision monitoring section for determining whether a collision has occurred between said voice burst and said packet data,

wherein, when said collision monitoring section detects a collision, said collision monitoring section provides an output to terminate said radio packet data communication, and when no collision is detected by said collision monitoring section, said radio data packet communication continues to completion.

13. A system for acquiring a channel in radio packet data communication for use with a base station and a mobile station, in communication with said base station, for transmitting a voice burst, comprising:

a receiver for receiving said voice burst and measuring a receiving level thereof;

a ranking section for ranking a receiving state of said receiver based on receiving levels of radio waves transmitted from said mobile station; and

a channel monitoring and control section for selecting a channel with a predetermined receiving state based on an output from said ranking section, and for monitoring the receiving state of the channel,

wherein, when said mobile station is determined not to be transmitting a voice burst on the channel, said channel is interrupted and packet data is transmitted thereover, and

wherein, when a voice burst is transmitted on said channel during transmission of said packet data, the transmission of packet data is suspended, and a second mobile station not transmitting a voice burst is identified, thereby to obtain an idle channel for radio packet data communication,

wherein said channel monitoring and control section comprises;

a postamble monitoring/supervising section for receiving an output from said ranking section and for monitoring postambles of a selected channel, such that packet data is transmitted when a postamble is received by said channel monitoring and control section; and

a collision monitoring section for determining whether a collision has occurred between said voice burst and said packet data,

wherein, when said collision monitoring section detects a collision, said collision monitoring section provides an output to terminate said radio packet data communication, and when no collision is detected by said collision monitoring section, said radio data packet communication continues to completion.

14. A communication system comprising:

a base station;

a first station in voice communication with said base station; and

a second station in data communication with said base station,

wherein said second station monitors said voice communication and identifies a predetermined period of said voice communication, said second station transmitting data packets during said predetermined period,

wherein, for packet data communication, said second station selectively uses an idle channel and other channels engaged, for voice communication, by mobile stations.

15. The system according to claim 14, wherein said first station comprises a first mobile station and said second station comprises a second mobile station, and

wherein said predetermined period comprises a silent period between audible sounds.

16. The system according to claim 15, wherein said silent period comprises a period between an ending voice burst and a beginning voice burst.

17. The system according to claim 14, wherein said voice communication and said data communication are made on a same channel.

18. The system according to claim 15, further comprising a plurality of first mobile stations, and said base station communicates with said first mobile stations on separate channels,

wherein said second mobile station includes means for monitoring said channels and for transmitting said data packets on selected ones of said separate channels which include said predetermined period.

19. The system according to claim 14, wherein said first station comprises a first mobile station and said second station comprises a second mobile station,

wherein said second mobile station monitors channels used by said first mobile station and selects one of a predetermined good quality channel for transmitting data packets in said packet data communication, and

wherein said second mobile station utilizes VOX control to detect a silent period in an engaged channel of said first mobile station for one of said transmitting of said data packets and inserting said data packets into said silent period.

20. A communication system comprising:

a base station;

a first station in voice communication with said base station;

a second station in data communication with said base station, wherein said second station monitors said voice communication and identifies a predetermined period of said voice communication, said second station transmitting data packets during said predetermined period, and wherein said first station comprises a first mobile station and said second station comprises a second mobile station, said predetermined period comprising a silent period between audible sounds; and

a plurality of first mobile stations, and said base station communicates with said first mobile stations on separate channels,

wherein said second mobile station includes means for monitoring said channels and for transmitting said data packets on selected ones of said separate channels which include said predetermined period, and means for ranking a receiving level of each of said channels.

21. The system according to claim 20, wherein said means for ranking comprises:

a power level measuring section for measuring a power level of said receiving levels of radio waves transmitted from said mobile station;

a power level comparing section for comparing said power level with a predetermined level;

a memory for storing levels of channels determined to have a level above said predetermined level and a respective channel number; and

a level selection section for selecting a channel having a highest level of said channels determined to have a level above said predetermined level, said level selection section providing an output to said means for monitoring.

22. The system according to claim 20, wherein said means for monitoring comprises:

a postamble monitoring/supervising section for receiving an output from said means for ranking and for monitoring postambles of a selected channel, such that a data packet is transmitted when a postamble is received by said means for monitoring; and

a collision monitoring section for determining whether a collision has occurred between said voice communication and said transmitting of data packets,

wherein, when said collision monitoring section detects a collision, said collision monitoring section provides an output to terminate said transmitting of data packets, and when no collision is detected by said collision monitoring section, said transmitting of said data packets continues to completion.

23. The system according to claim 21, wherein said means for monitoring comprises:

a postamble monitoring/supervising section for receiving an output from said means for ranking and for monitoring postambles of a selected channel, such that a data packet is transmitted when a postamble has been received by said means for monitoring; and

a collision monitoring section for determining whether a collision has occurred between said voice communication and said transmitting of data packets,

wherein, when said collision monitoring section detects a collision, said collision monitoring section provides an output to terminate said transmitting of data packets, and when no collision is detected by said collision monitoring section, said transmitting of said data packets continues to completion.

24. A method for acquiring a channel in radio packet data communication system including a base station and a mobile station, in communication with said base station, for transmitting a voice burst, comprising:

receiving said voice burst and measuring a receiving level thereof;

ranking a receiving state based on receiving levels of radio waves transmitted from said mobile station;

selecting a channel with a predetermined receiving state based on said ranking, and monitoring the receiving state of the channel;

determining whether said mobile station is not transmitting a voice burst on the channel;

based on said determining, interrupting said channel and transmitting packet data thereover; and

when said determining determines a voice burst is transmitted on said channel during transmission of said packet data, suspending the transmission of said packet data, and identifying a second mobile station not transmitting a voice burst, thereby to obtain an idle channel for radio packet data communication.

25. The method according to claim 24, further comprising:

when said idle channel obtained for the packet data transmission is used for voice communication before termination of packet data transmission, suspending the transmission of packet data;

monitoring for a burst which indicates termination of the voice burst; and

interrupting a channel not transmitting a voice burst.

26. The method according to claim 24, further comprising:

when the voice burst is terminated and a silent state is determined, determining that the channel is usable, and transmitting packet data.

27. The method according to claim 26, further comprising:

when starting of the voice burst as a talking state is obtained again, confirming a state where no burst is transmitted on the channel;

determining that said channel cannot be used; and

terminating the packet data transmission.

28. The method according to claim 24, wherein said ranking comprises:

measuring a power level of said receiving levels of radio waves transmitted from said mobile station;

comparing said power level with a predetermined level; and

storing levels of the channels determined to have a level above said predetermined level and a respective channel number, and

wherein said selecting comprises;

selecting a channel having a highest level of said channels determined to have a level above said predetermined level.

29. The method according to claim 24, wherein said determining comprises:

monitoring postambles of a selected channel to control transmission of packet data; and

determining whether a collision has occurred between said voice burst and said packet data,

wherein, when a collision is detected, said radio packet data transmission is terminated, and when no collision is detected, said radio packet data transmission continues to completion.