Delay correction system for wireless telephone system

• US 6,631,142 B2
• Filed: 02/14/2000
• Issued: 10/07/2003
• Est. Priority Date: 03/17/1999
• Status: Expired due to Term

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Tanishima, Yasuo, Miyamoto, Shoichi
• Primary Examiner(s): Yao, Kwang Bin
• Assistant Examiner(s): NGUYEN, HANH N
• Application Number:
  US09/503,705
• Publication Number:
  US 20010040879A1
• Time in Patent Office: 1,331 Days
• Field of Search: 370/350, 370/519, 370/517, 370/503, 370/508, 370/509, 370/512, 370/337, 370/336, 370/335, 370/347, 375/354, 375/365, 375/371, 455/525, 455/502, 455/524, 455/67.1, 455/423, 455/522
• US Class Current: 370/508
• CPC Class Codes: H04W 56/0045 compensating for timing error by altering transmission time

Abstract

A delay correction system is used for a wireless telephone system in which a base station apparatus and at least one subscriber apparatus carry out transmitting and receiving operations via respective communication means, in conformance with a time division multiple access (TDMA) system using the base station apparatus as a synchronization reference. The delay correction system includes a measuring instruction input unit for inputting a delay measuring instruction which instructs a delay measurement, a delay measuring unit for measuring a delay quantity between the base station apparatus and the subscriber apparatus, and a first timing adjusting unit, provided in the subscriber apparatus, for receiving transmitting information which is to be sent to the base station apparatus at an allocated time slot, and for adjusting a timing of the transmitting information depending on the delay quantity before sending the transmitting information.

Claims

1. A delay correction system for a wireless telephone system in which a base station apparatus and at least one subscriber apparatus carry out transmitting and receiving operations via respective communication means, in conformance with a time division multiple access (TDMA) system using the base station apparatus as a synchronization reference, said delay correction system comprising:

measuring instruction input means for inputting a delay measuring instruction which instructs a delay measurement based on a new registration or a moving of the subscriber apparatus;

delay measuring means, responsive to the delay measuring instruction, for measuring a delay quantity between the base station apparatus and the subscriber apparatus based on a signal received over a control channel; and

first timing adjusting means, provided in the subscriber apparatus, for receiving transmitting information which is to be sent to the base station apparatus at an allocated time slot, and for adjusting a timing of the transmitting information depending on the delay quantity before sending the transmitting information.

2. The delay correction system as claimed in claim 1, wherein said measuring instruction input means comprises:

measuring instruction transmitting means for transmitting a delay measuring instruction depending on an input of a measuring start instruction; and

correcting instruction accepting means for accepting and input of a delay correcting instruction and transmitting the measuring start instruction to said measuring instruction transmitting means depending on the acceptance of the delay correcting instruction.

3. The delay correction system as claimed in claim 1, wherein said delay measuring means measures the delay quantity between the base station apparatus and the subscriber apparatus using a unique word included in the signals received over the control channel.

4. The delay correction system as claimed in claim 1, wherein said measuring instruction input means inputs the delay measuring instruction in response to a position register request from the subscriber apparatus or an instruction issued from a maintenance management system which is coupled to the base station apparatus.

5. A delay correction system for a wireless telephone system in which a base station apparatus and at least one subscriber apparatus carry out transmitting and receiving operations via respective communication means, in conformance with a time division multiple access (TDMA) system using the base station apparatus as a synchronization reference, said delay correction system comprising:

measuring instruction input means for inputting a delay measuring instruction which instructs a delay measurement;

delay measuring means for measuring a delay quantity between the base station apparatus and the subscriber apparatus; and

first timing adjusting means, provided in the subscriber apparatus, for receiving transmitting information which is to be sent to the base station apparatus at an allocated time slot, and for adjusting a timing of the transmitting information depending on the delay quantity before sending the transmitting information;

wherein said delay measuring means comprises;

first signal transmitting means, provided in the subscriber apparatus, for transmitting a measuring signal which is used as a reference when measuring the delay quantity, depending on the delay measuring instruction from said measuring instruction input means;

subscriber and measuring signal communicating means, provided in the subscriber apparatus, for exchanging the measuring signal with the base station apparatus;

base station and measuring signal communicating means, provided in the base station apparatus, for exchanging the measuring signal with the subscriber apparatus;

loop-back means, provided in the base station apparatus, for looping back the measured signal which is received via said base station end measuring signal communicating means after a predetermined time, as a response signal to the subscriber apparatus; and

first delay detecting means, provided in the subscriber apparatus, for detecting the delay quantity of the transmission delay between the subscriber apparatus and the base station apparatus, based on an error between a timing at which the response signal should be received and a timing at which the response signal is actually received from said subscriber end measuring signal communicating means, said first timing adjusting means adjusting the transmission timing based on the delay quantity which is received from said first delay detecting means.

6. The delay correction system as claimed in claim 5, wherein:

said base station end measuring signal communicating means comprises;

first signal inserting means for securing, as measuring signal transmitting channels, two successive time slots of a transmission period provided by said communication means of the base station apparatus, and transmitting the measuring signal in the measuring signal transmitting channels; and

first signal separating means for securing, as measuring signal receiving channels, two successive time slots of a reception period provided by said communications means, and separating the signal received in the measuring signal receiving channels,

and said subscriber end measuring signal communicating means comprises;

second signal inserting means for securing, as measuring signal transmitting channels, two successive time slots of a transmission period provided by said communication means of the subscriber apparatus, and transmitting the measuring signal in the measuring signal transmitting channels; and

second signal separating means for securing, as measuring signal receiving channels, two successive time slots of a reception period provided by said communication means, and separating the measuring signal received in the measuring signal receiving channels.

7. The delay correction system as claimed in claim 5, wherein said base station and measuring signal communicating means and said subscriber end measuring signal communicating means communicate the measuring signals using frequency bands which are different from those used by the respective communication means of the other of said base station and measuring signal communicating means and said subscriber end measuring signal communicating means.

8. A delay correction system for a wireless telephone system in which a base station apparatus and at least one subscriber apparatus carry out transmitting and receiving operations via respective communication means, in conformance with a time division multiple access (TDMA) system using the base station apparatus as a synchronization reference, said delay correction system comprising:

measuring instruction input means for inputting a delay measuring instruction which instructs a delay measurement;

delay measuring means for measuring a delay quantity between the base station apparatus and the subscriber apparatus; and

first timing adjusting means, provided in the subscriber apparatus, for receiving transmitting information which is to be sent to the base station apparatus at an allocated time slot, and for adjusting a timing of the transmitting information depending on the delay quantity before sending the transmitting information;

wherein said delay measuring means comprises;

second signal transmitting means, provided in the base station apparatus, for transmitting a measuring signal which is used as a reference when measuring the delay quantity, depending on the delay measuring instruction from said measuring instruction input means;

base station end measuring signal communicating means, provided in the base station apparatus, for exchanging a measuring signal with the subscriber apparatus;

measuring signal respond means, provided in the subscriber apparatus, for transmitting the measuring signal to the base station apparatus via said subscriber end measuring signal communicating means in a time slot allocated for the subscriber apparatus;

second delay detecting means, provided in the base station apparatus, for detecting the delay quantity of the transmission delay between the subscriber apparatus and the base station apparatus, based on an error between a timing at which a response signal with respect to the measuring signal should be received and a timing at which the response signal is actually transmitted by said measuring signal respond means; and

second delay notifying means, provided in the base station apparatus, for transmitting delay information which indicates the delay quantity detected by said second delay detecting means to the subscriber apparatus via said base station and measuring signal communicating means,

said first timing adjusting means adjusting the transmission timing base on the delay quantity which is indicated by the delay information received from said subscriber end measuring signal communicating means.

9. The delay correction system as claimed in claim 8, wherein:

said base station end measuring signal communicating means comprises;

first signal inserting means for securing, as measuring signal transmitting channels, two successive time slots of a transmission period provided by said communication means of the base station apparatus, and transmitting the measuring signal in the measuring signal transmitting channels; and

first signal separating means for securing, as measuring signal receiving channels, two successive time slots of a reception period provided by said communication means, and separating the signal received in the measuring signal receiving channels,

and said subscriber end measuring signal communicating means comprises;

second signal inserting means for securing, as measuring signal transmitting channels, two successive time slots of a transmission period provided by said communication means of the subscriber apparatus, and transmitting the measuring signal in the measuring signal transmitting channels; and

second signal separating means for securing, as measuring signal receiving channels, two successive time slots of a reception period provided by said communication means, and separating the measuring signal received in the measuring signal receiving channels.

10. The delay correction system as claimed in claim 8, wherein said base station end measuring signal communicating means and said subscriber end measuring signal communicating means communicate the measuring signals using frequency bands which are different from those used by the respective communication means of the other of said base station end measuring signal communicating means and said subscriber end measuring signal communicating means.

11. A delay correction system for a wireless telephone system in which a base station apparatus and at least one subscriber apparatus carry out transmitting and receiving operations via respective communication means, in conformance with a time division multiple access (TDMA) system using the base station apparatus as a synchronization reference, said delay correction system comprising:

measuring instruction input means for inputting a delay measuring instruction which instructs a delay measurement;

delay measuring means for measuring a delay quantity between the base station apparatus and the subscriber apparatus; and

first timing adjusting means, provided in the subscriber apparatus, for receiving transmitting information which is to be sent to the base station apparatus at an allocated time slot; and

for adjusting a timing of the transmitting information depending on the delay quantity before sending the transmitting information;

wherein said measuring instruction input means comprises;

measuring instruction transmitting means for transmitting a delay measuring instruction depending on an input of a measuring start instruction; and

register request detecting means for detecting a position register request from the subscriber apparatus and transmitting the measuring start instruction to said measuring instruction transmitting means in response to the position register request.

12. A delay correction system for a wireless telephone system in which a base station apparatus and at least one subscriber apparatus carry out transmitting and receiving operations via respective communication means, in conformance with a time division multiple access (TDMA) system using the base station apparatus as a synchronization reference, said delay correction system comprising:

measuring instruction input means for inputting a delay measuring instruction which instructs a delay measurement;

delay measuring means for measuring a delay quantity between the base station apparatus and the subscriber apparatus; and

first timing adjusting means, provided in the subscriber apparatus, for receiving transmitting information which is to be sent to the base station apparatus at an allocated time slot, and for adjusting a timing of the transmitting information depending on the delay quantity before sending the transmitting information;

wherein said measuring input means comprises;

measuring instruction transmitting means for transmitting a delay measuring instruction depending on an input of a measuring start instruction; and

establish request detecting means for detecting a link channel establish request from the subscriber apparatus and transmitting the measuring start instruction to said measuring instruction transmitting means depending on the detection of the link channel establish request.

21. The delay correction system as claimed in claim 12, wherein said measuring instruction input means comprises:

measuring instruction transmitting means for transmitting a delay measuring instruction depending on an input of a measuring start instruction; and

establish request detecting means for detecting a link channel establish request from the subscriber apparatus and transmitting the measuring start instruction to said measuring instruction transmitting means depending upon the detection of the link channel establish request.

13. A delay correction system for a wireless telephone system in which a base station apparatus and at least one subscriber apparatus carry out transmitting and receiving operations via respective communication means, in conformance with a time division multiple access (TDMA) system using the base station apparatus as a synchronization reference, said delay correction system comprising:

measuring instruction input means for inputting a delay measuring instruction which instructs a delay measurement;

delay measuring means for measuring a delay quantity between the base station apparatus and the subscriber apparatus; and

time slot correcting means, provided in the base station apparatus, for adjusting a time position of a signal received from the subscriber apparatus depending on the delay quantity, and moving the time position of the received signal to an appropriate time slot.

14. The delay correction system as claimed in claim 13, wherein said delay measuring means comprises:

first signal transmitting means, provided in the subscriber apparatus, for transmitting a measuring signal which is used as a reference when measuring the delay quantity, depending on the delay measuring instruction from said measuring instruction input means;

subscriber end measuring signal communicating means, provided in the subscriber apparatus, for exchanging the measuring signal with the base station apparatus;

base station end measuring signal communicating means, provided in the base station apparatus, for exchanging the measuring signal with the subscriber apparatus;

loop-back means, provided in the base station apparatus, for looping back the measured signal which is received via said base station end measuring communicating means after a predetermined time, as a response signal to the subscriber apparatus; and

first delay detecting means, provided in the subscriber apparatus, for detecting the delay quantity of the transmission delay between the subscriber apparatus and the base station apparatus, based on an error between a timing at which the response signal should be received and a timing at which the response signal is actually received from said subscriber end measuring signal communicating means,

said time slot correcting means receiving the delay information from said base station end measuring signal communicating means, and adjusting the time position of the received signal.

15. The delay correction system as claimed in claim 14, wherein:

said base station end measuring signal communicating means comprises;

first signal inserting means for securing, as measuring signal transmitting channels, two successive time slots of a transmission period provided by said communication means of the base station apparatus, and transmitting the measuring signal in the measuring signal transmitting channels; and

first signal separating means for securing, as measuring signal receiving channels, two successive time slots of a reception period provided by said communication means, and separating the signal received in the measuring signal receiving channels,

and said subscriber end measuring signal communicating means comprises;

second signal inserting means for securing, as measuring signal transmitting channels, two successive time slots of a transmission period provided by said communication means of the subscriber apparatus, and transmitting the measuring signal in the measuring signal transmitting channels; and

second signal separating means for securing, as measuring signal receiving channels, tow successive time slots of a reception period provided by said communication means, and separating the measuring signal received in the measuring signal receiving channels.

16. The delay correction system as claimed in claim 14, wherein said base station end measuring signal communicating means and said subscriber end measuring signal communicating means communicate the measuring signals using frequency bands which are different from those used by the respective communication means of the other of said base station end measuring signal communicating means and said subscriber end measuring signal communicating means.

17. The delay correction system as claimed in claim 13, wherein said delay measuring means comprises:

second signal transmitting means, provided in the base station apparatus, for transmitting a measuring signal which is used as s reference when measuring the delay quantity, depending on the delay measuring instruction from said measuring instruction input means;

base station end measuring signal communicating means, provided in the base station apparatus, for exchanging a measuring signal with the base station apparatus;

measuring signal respond means, provided in subscriber apparatus, for transmitting the measuring signal to the base station apparatus via said subscriber end measuring signal communicating means in a time slot allocated for the subscriber apparatus; and

second delay detecting means, provided in the base station apparatus, for detecting the (delay quantity of the transmission delay between the subscriber apparatus and the base station apparatus, based on an error between a timing at which a response signal with respect to the measuring signal should be received and a timing signal at which the response signal is actually transmitted by said measuring signal respond means,

said time slot correcting means adjusting the time position of the received information, based on the delay quantity detected by said second delay detecting means.

18. The delay correction system as claimed in claim 17, wherein

said base station end measuring signal communicating means comprises:

first signal inserting means for securing, as measuring signal transmitting channels, two successive time slots of a transmission period provided by said communications means of the base station apparatus, and transmitting the measuring signal in the measuring signal transmitting channels; and

first signal separating means for securing, as measuring signal receiving channels, two successive time slots of a reception period provided by said communication means, and separating the signal received in the measuring signal receiving channels,

and said subscriber end measuring signal communicating means comprises;

second signal inserting means for securing, as measuring signal transmitting channels, two successive time slots of a transmission period provided by said communication means of the subscriber apparatus, and transmitting the measuring signal in the measuring signal transmitting channels; and

second signal separating means for securing, as measuring signal receiving channels, two successive time slots of a reception period provided by said communication means, and separating the measuring signal received in the measuring signal receiving channels.

19. The delay correction system as claimed in claim 17, wherein said base station end measuring signal communicating means and said subscriber end measuring signal communicating means communicate the measuring signals using frequency bands which are different from those used by the respective communication means of the other of said base station end measuring signal communicating means and said subscriber end measuring signal communicating means.

20. The delay correction system as claimed in claim 17, wherein said measuring instruction input means comprises:

measuring instruction transmitting means for transmitting a delay measuring instruction depending on an input of a measuring start instruction; and

register request detecting means for detecting a position register request from the subscriber apparatus and transmitting the measuring start instruction to said measuring instruction transmitting means in response to the position register request.

22. The delay correction system as claimed in claim 13, wherein said measuring instruction input means comprises:

measuring instruction transmitting means for transmitting a delay measuring instruction depending on an input of a measuring start instruction; and

correcting instruction accepting means for accepting an input of a delay correcting instruction and transmitting the measuring start instruction to said measuring instruction transmitting means depending on the acceptance of the delay correcting instruction.

23. A delay correction system for a wireless telephone system in which a base station apparatus and at least one subscriber apparatus carry out transmitting and receiving operations, in conformance with a time division multiple access (TDMA) system using the base station apparatus as a synchronization reference, said subscriber apparatus comprising:

communication means for transmitting and receiving signals with respect to the base station apparatus;

communication control means for controlling the operation of said communication means in conformance with the TDMA system;

second timing adjusting means for receiving transmitting information which is to be sent to the base station apparatus and adjusting a transmission timing depending on and adjusting value which is specified by an input adjusting instruction;

establishment request means for repeatedly instructing said communication control means that a link channel establish request is issued;

transmission timing search means, which starts to operate depending on a transmission of the link channel establish request by said communication control means, for changing the adjusting value depending on whether or not said communication means received a response corresponding to the link channel establish request, and for transmitting the adjusting instruction (which specifies the adjusting value to said second timing adjusting means; and

channel allocation monitoring means for monitoring exchange of signals between said communication means and the base station apparatus, and stopping an operation of said establishment request means depending on a detection of a response corresponding to the link channel establish request.

24. A delay correction system for a wireless communication system in which a base station apparatus and at least one subscriber apparatus carry out transmitting and receiving operations via respective communication means, in conformance with a time division multiple access (TDMA) system using the base station apparatus as a synchronization reference, said delay correction system comprising:

a measuring instruction input unit inputting a delay measuring instruction which instructs a delay measurement based on a new registration of a moving of the subscriber apparatus;

a delay measuring unit responsive to the delay measuring instruction, measuring a delay quantity between the base station apparatus and the subscriber apparatus based on a signal received over a control channel; and

a timing adjusting unit, provided in the subscriber apparatus, receiving transmitting information which is to be sent to the base station apparatus at an allocated time slot, and adjusting a timing of the transmitting information depending on the delay quantity before sending the transmitting information.

25. The delay correction system as claimed in claim 24, wherein said measuring instruction input unit inputs the delay measuring instruction in response to a position register request or an instruction issued from a maintenance management system which s coupled to the base station apparatus.

26. A delay correction system for a wireless communication system in which a base station apparatus and at least one subscriber apparatus carry out transmitting and receiving operations via respective communication means, in conformance with a time division multiple access (TDMA) system using the base station apparatus as a synchronization reference, said delay correction system comprising:

a measuring instruction input unit inputting a delay measuring instruction which instructs a delay measurement;

a delay measuring unit measuring a delay quantity between the base station apparatus and the subscriber apparatus; and

a time slot correcting unit, provided in the base station apparatus, adjusting a time position of a signal received from the subscriber apparatus depending on the delay quantity, and moving the time position of the received signal to an appropriate time slot.

27. A subscriber apparatus for a wireless communication system in which a base station apparatus and at least one subscriber apparatus carry out transmitting and receiving operations, in conformance with a time division multiple access (TDMA) using the base station apparatus as a synchronization reference, said subscriber apparatus comprising:

a communication unit transmitting and receiving signals with respect to the base station apparatus;

a communication control unit controlling the operation of said communication unit in conformance with the TDA system;

a timing adjusting unit receiving transmitting information which is to be sent to the base station apparatus and adjusting a transmission timing depending on an adjusting value which is specified by an input adjusting instruction;

an establishment request unit repeatedly instructing said communication control unit that a link channel establish request is issued;

a transmission timing search unit which starts to operate depending on a transmission of the link channel establish request by said communication control unit, changes the adjusting value depending on whether or not said communication unit received a response corresponding to the link channel establish request, and transmits the adjusting instruction which specifies the adjusting value to said timing adjusting unit; and

a channel allocation monitoring unit monitoring exchange of signals between said communication unit and the base station apparatus, and stopping an operation of said establishment request unit depending on a detection of a response corresponding to the link channel establish request.