CA1294332C - Method for formatting an answer signal in data transmission - Google Patents
Method for formatting an answer signal in data transmissionInfo
- Publication number
- CA1294332C CA1294332C CA000548456A CA548456A CA1294332C CA 1294332 C CA1294332 C CA 1294332C CA 000548456 A CA000548456 A CA 000548456A CA 548456 A CA548456 A CA 548456A CA 1294332 C CA1294332 C CA 1294332C
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- Canada
- Prior art keywords
- data
- signal
- answer signal
- block
- answer
- Prior art date
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- Expired - Fee Related
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Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/1607—Details of the supervisory signal
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/1607—Details of the supervisory signal
- H04L1/1614—Details of the supervisory signal using bitmaps
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/1607—Details of the supervisory signal
- H04L1/1621—Group acknowledgement, i.e. the acknowledgement message defining a range of identifiers, e.g. of sequence numbers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/1607—Details of the supervisory signal
- H04L1/1664—Details of the supervisory signal the supervisory signal being transmitted together with payload signals; piggybacking
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/1607—Details of the supervisory signal
- H04L1/1671—Details of the supervisory signal the supervisory signal being transmitted together with control information
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/1607—Details of the supervisory signal
- H04L1/1685—Details of the supervisory signal the supervisory signal being transmitted in response to a specific request, e.g. to a polling signal
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/1607—Details of the supervisory signal
- H04L1/1692—Physical properties of the supervisory signal, e.g. acknowledgement by energy bursts
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/18—Automatic repetition systems, e.g. Van Duuren systems
- H04L1/1809—Selective-repeat protocols
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/18—Automatic repetition systems, e.g. Van Duuren systems
- H04L1/1829—Arrangements specially adapted for the receiver end
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W28/00—Network traffic management; Network resource management
- H04W28/02—Traffic management, e.g. flow control or congestion control
- H04W28/06—Optimizing the usage of the radio link, e.g. header compression, information sizing, discarding information
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Mobile Radio Communication Systems (AREA)
- Detection And Prevention Of Errors In Transmission (AREA)
- Communication Control (AREA)
- Telephonic Communication Services (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A method for formatting an answer signal allows correct data communication even when such data communication is effected through transmission lines under bad conditions such as in a mobile radio communication system, e.g., automobile radio communication system. The answer signal formatting method forms a plurality of answer signals (ACK or NAK signals) sent from a called party in response to a ringing signal from a calling party, between data blocks, so that an answer signal can be received without fail before the data blocks are completely confirmed by the calling party.
A method for formatting an answer signal allows correct data communication even when such data communication is effected through transmission lines under bad conditions such as in a mobile radio communication system, e.g., automobile radio communication system. The answer signal formatting method forms a plurality of answer signals (ACK or NAK signals) sent from a called party in response to a ringing signal from a calling party, between data blocks, so that an answer signal can be received without fail before the data blocks are completely confirmed by the calling party.
Description
1'~9433Z
SPECIFICATION
METHOD FOR FORMATTING ANSWER SIGNAL
IN DATA TRANSMISSION
BACKGROUND OF THE INVENTION
The pre~ent invention relates to a method for formatting an answer signal in data CommUniCation~ and more particularly to a method for formatting the answer signal for use in mobile data communication in a public automobile telephone system.
Automobile telephone systems have already been in commercia-l u~e in U.S.A., Japan, Canada, and various European countries. ~owever, mobile radio data communication has jU~t begun it~ application to practical use. It is well ~nown in the art that since the mobile radio data communication ha~ radio transmission lines, data errors are frequently caused by Rayleigh fading and man-made noise. To solve such a problem, modems are employed WhiCh have a special error control function that cannot be handled by a computer. More specifically, the transmission process in data communication requires a function to confirm a data reception with ~ignals ~uch as "ACK" (a signal indicating receipt of error-free data) and "NAK" (a ~ignal indicating reCeipt of error-containing data) which indicate whether the reception is acceptable or not between the modems, as described in "Bell System Data Communication Technical reference" P~B41106 and PUB41202, "New Data Transmission System" written by Toshio Soejima and published by San-gyo Tsoho K.K. on August 31, 1982, pages 216 through 218, and Japanese Patent Application No. 60-189767, which wa~ published on March 61, 1987 under No. 62-51326, for example.
In the mobile da~a communication, an ACK signal or a NA~ signal is added to the terminal end of an answer slgnal for transmission.
However, with an ACK signal or a NAK signal added to the terminal end of an answer signal, data communicatlon between computers cannot be initiated until the ACK or NAK signal i8 received even if a calling mode is establishèd after the an wer signal ha~ been received by a calling party. Therefore, until the ACK or NAK
signal is recelved, data cannot be transmitted to a called party, and the executlon transmlssion efflclency is low. In the event that an ACK or NAK si~nal added to an answer signal is dropped due to fading, city nolse, or the like, the next communlcation procedure cannot be started, and hence the data communication falls in the initial process.
SUUMARY OF THE INVENTION
In view of the aforesaid drawbacks, it ls an object of the present invention to provide a method for formatting an answer signal in data communication which is capable of increasing an execution transmission efficiency by en~ering data communication substantially at the same time that a calling mode is established.
3a~
According to the present invention, there is provided method for formatting an answer signal in mobile radio communication, comprising the steps of forming a block of answer signal indicating reception of data transmitted from a transmission side, dividing the block of an~wer signal into a plurality of blocks Of data, adding single predetermined signals indicating a re~ult of reception of data to terminal ends of the blocks of data, respectively, forming a signal block composed of a combination of the blocks of data and the predetermined ~ignal~, modulating the signal block, transmitting the modulated signal block, receiving and demodulating the transmitted signal block, and confirming an answer signal of the modulated signal block and recognizing a block of data.
The above and other objects, feature~ and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which a preferred embodiment of the present invention is shown by way of illustrative example.
BRIEF DESCRIPTION OF THE DRAWINGS
~ig. 1 i~ a block diagram of a mobile radio data communication system;
Fig. 2 iS a diagram showing a transmission control sequence in data communicatlon;
Fig. 3 is a diagram of an answer signal transmission lZ94332 f ormat;
Fig. 4a i~ a block diagram of a data modem in a land ~tation employing a method for formatting an answer signal of the present invention; and Fig. 4b is a block diagram of a data modem in a mobile employing a method for formatting an an~wer ~ignal of the present invention.
DES~RIPTION OF T~E PREFERRED EMBODIMENT
Fig. 1 schematically show~ a mobile radio data communication sy~tem comprl~ing a computer 1, a telephone set 2, a data modem 3, a public circuit 4, a mobile telecommunication ~witching office (MTSO) 5, cell ~ites 6, a mobile 7, an automo~ile telephone transmitter/receiver unit (TRU) 8~ a data modem 9~ a control unit (CU) 10, and a computer 11. The component~ rangin~ from the computer 1 to the cell sites 6 are in a land station, and components ranging from the TRU 8 tO the computer 11 are on the mobile 7.
Data communication between the computer ] in the land ~tation and the computer 11 on the mobile 7 will be described with reference to Fig. 1. While the computer 1 and the telephone ~et 2 are coupled to the data modem 3, the connection between the computer 1 and the data modem 3 becomes effective by switching to a data mode. A block of data i~ sent from the computer 1 to the data modem 3 in which it is encoded by an error-correcting code. The data ~2S~4~32 block i~ then ~ent frorn the data modem 3 to the public circuit 4. The data block i5 then transmitted from the MTSo 5 and a cell site 6 to tlle mobile 7 where it is received by the TRU 8. The received data i~ thereafter decoded by the data modem 9. If the received data is correct data, then it is sent to the computer 11. If the received data contains an error or error~, the data modem g a~ks the land station to resend the ~ame data block.
This process i~ repeated to transmit data from the computer 1 in the land station to the data modem 9 on the mobile 7. Data can be transmitted from the computer 11 on the mobile 7 to the computer 1 in the land station in the same manner as described above. It is also possible to effect telephonic communication between the telephone set 2 and a control unit (hand set) on the mobile 7.
~ A communication sequence using the network shown in Fig. 1 will be de~cribed with reference to Fig. 2.
Fir~t, the telephone set 2 i~ removed from it hook toff hook) by the u~er to call the mobile from the land station. A dial tone requesting dialing signals is heard, and the user dials the directory number of the mobile.
The mobile receive~ a ringing tone and detects a ringer for thereby confirming the call. The land station then hears a ring-back tone from the mobile. Thereafter, the mobile sends an answer signal (answer tone~ which is a single signal to the land station.
Fig. 3 illustrates an answer signal transmission format according to an embodiment of the pre~ent invention. Designated at 1, 3, 5, 7 are single answer signalfi, and 2, 4, 6, 8 are ACK siynals (which may be NAK
~ignal~). In the illu~trated transmission format, the answer ~ignal~ 1, 3, 5, 7 and the A~K signal~ 2, 4, 6, 8 are alternately inserted. However, the an~wer ~ignal~ and the ACK (or NAK) signals may be in~erted in other combinations. The time period from the beginning of the an~wer signal 1 to the terminal end of the ~CK signal 8 i~
substantially the same as the conventional time period.
Therefore, by u~ing the an~wer ~ignal tran~mi~ion format according to the embodiment of the invention, when the called party an~wer~ the call, the calling party establishes a calling mode with the answer signal 1 and immediately receives the next ACK signal 2 in a ~hort period of time to confirm the receipt of the tran~mi~ion.
Thu~, the calling party and the called party can immediately initiate data communication. Even if the ACK
~ignal 2 i~ dropped due to fading, city noi~e, or the like, the second ACK signal 4 can be received, so that the initial proces~ can be effected without fail.
The method for formatting the an~wer ~ignal of the invention is employed in the data modem 3 in the land ~tation and the data modem 9 on the mobile 7. Fig. 4a shows in block form the data modem 3 in the land station, and Fig. 4b show~ in block form the data modem 9 on the mobile. The data modem 3 includes a processor 30], an RS-23ZC interface a~sembly 310, a power source 313, a modemas~ernbly 317, and an ORG signal/ringer detector 326. The computer 1 shown in Fig. 1 is connected to an RS-232C
interface port 342, the telephone set 2 to a TELSET
interface 341, and the public circuit 4 to a TELCO
interface 34~.
Operation to transmit data from the data mod-em 3 in the land station to the mobile 7 will now be described below. When the data modem 3 is energized, an ORG/ANS
logic function unit 325 detect~ whether the data modem 3 is in a transmission mode or a reception mode. It is assumed here that the data modem 3 is in a transmission mode. The transmi~sion mode is sent through a peripheral interface 322 to a CPU 302 in the proces~or 301, and the CPU 302 ackowledges the starting of data transmi~sion.
Then, the CPU 302 checks the RS-232C interface assembly 310 which comprises a driver & receiver 311 and a data communication interface 313 to see if the computer 1 connected to the RS-232C interface port 342 i~ ready or not. Data to be transmitted from the computer 1 i~ read into a RAM 304 in the processor 301 in which it is encoded With an error-correcting code to form a data block. For telephonic communication, ~ince the data modem is connected to telephone ~et 2 via the T~LSET interface 340, a driver 330 is operated to shift a line switch 329 to the TELCO interface 341 for connection to the public circuit 4. The CPU 302 waits for an ACK ~ignal from the mobile 7.
1~94332 The ACK signal is received through the TELCO interface 341, demodulated by the modem assernbly 317, and fed to the processor 301 through the peripheral interface 319. Since the modem assembly 317 is of a known nature, its operation will not be described. When the ACK signal is received, the CPU 302 transmits the block data stored in the RAM 304 to the mobile 7.
As described above, an answer signal transmission format compri~es a combination of answer signal~ and ACK
or NAK signals in the initial process of data communication. Therefore, data communication can be initiated at substantially the same time that a calling mode is established, and the AC~ or NAK signals can reliably be received even when fading or city noise is generated, so that the system can enter a next communication process without fail.
The data block is sent by the CPU 302 from the RAM
304 through the peripheral interface 319, the modem 318, the line switch 329, and the TELCO interface 341 to the public circuit 4, from which the data block is transmitted via the MTSO 5 and the cell site 6 to the mobile 7.
Successive data blocks are similarly encoded with an error-correcting code by the RAM 304 and then transmi~ted.
Reception by the mobile 7 of the transmitted data will be described with reference to Figs. 1 and 4b. The mobile data modem includes a processor 901, an RS-232C
interface assembly 910, a power source 913, and a modem 3.32 a~sembly 917. The computer ].1 shown in Fig. 1 is connected to an RS-232C interface port 942, and the automobile telephone tran~mitter/receiver unit (TRU) 8 and the control unit (CU) 10 are connected to a TRU/CU
interface port 940. A ringing signal tran~mitted from the la.nd station is ~ent to the modem as~embly 917 through the TRU/CU interface port 940 and an audio path switch 932 The received modulated data i~ then demodulated by the modem a~sembly 917 and fed to a CPU 902 in the proces~or 901 via a peripheral interface 9l.9. When the CPu 902 find~ the received data to be a ringing signal, the CPU
. 902 send~ the signal to a RAM 904 and i~sue~ ACK signals a~ shown in Fig. 3. The ACK ~ignal~ are tran~mitted through the modem assembly 917, the audio path ~witch 932, and the TRUlCU interface port 940 to the land ~tation.
Upon con~irming the ACK signals, the land station transmits a block of data which i~ sent through the T~U/CU interface port 940 and the audio path switch 932 to the modem a~sembly 917. The modem assembly 917 demodulate~ the received modulated data block, which i~ ~ent via the peripheral interface 919 to the RAM 904 in the processor 901. The audio path switch 932 effect~ path switching for audio ~ignal~ between a data mode and a conver~ation mode.
The CPU 902 encodes the data which has been stored in the RAM 904. When encoded and properly received, the data i~
fed to the computer 11 through the RS~232C interface assembly 910 and the RS-232C interface port 942.
lZ~33;~
Successive data blocks from the computer 1 in the land station are similarly transmitted to the mobile computer 11. Data transmission from the mobile computer 11 to the land computer 1 is also similarly carried out.
Although a certain preferred embodiment has been shown and described, it should be understood that many changes and modifications may be made therein without departing from the scope of the appended claim.
SPECIFICATION
METHOD FOR FORMATTING ANSWER SIGNAL
IN DATA TRANSMISSION
BACKGROUND OF THE INVENTION
The pre~ent invention relates to a method for formatting an answer signal in data CommUniCation~ and more particularly to a method for formatting the answer signal for use in mobile data communication in a public automobile telephone system.
Automobile telephone systems have already been in commercia-l u~e in U.S.A., Japan, Canada, and various European countries. ~owever, mobile radio data communication has jU~t begun it~ application to practical use. It is well ~nown in the art that since the mobile radio data communication ha~ radio transmission lines, data errors are frequently caused by Rayleigh fading and man-made noise. To solve such a problem, modems are employed WhiCh have a special error control function that cannot be handled by a computer. More specifically, the transmission process in data communication requires a function to confirm a data reception with ~ignals ~uch as "ACK" (a signal indicating receipt of error-free data) and "NAK" (a ~ignal indicating reCeipt of error-containing data) which indicate whether the reception is acceptable or not between the modems, as described in "Bell System Data Communication Technical reference" P~B41106 and PUB41202, "New Data Transmission System" written by Toshio Soejima and published by San-gyo Tsoho K.K. on August 31, 1982, pages 216 through 218, and Japanese Patent Application No. 60-189767, which wa~ published on March 61, 1987 under No. 62-51326, for example.
In the mobile da~a communication, an ACK signal or a NA~ signal is added to the terminal end of an answer slgnal for transmission.
However, with an ACK signal or a NAK signal added to the terminal end of an answer signal, data communicatlon between computers cannot be initiated until the ACK or NAK signal i8 received even if a calling mode is establishèd after the an wer signal ha~ been received by a calling party. Therefore, until the ACK or NAK
signal is recelved, data cannot be transmitted to a called party, and the executlon transmlssion efflclency is low. In the event that an ACK or NAK si~nal added to an answer signal is dropped due to fading, city nolse, or the like, the next communlcation procedure cannot be started, and hence the data communication falls in the initial process.
SUUMARY OF THE INVENTION
In view of the aforesaid drawbacks, it ls an object of the present invention to provide a method for formatting an answer signal in data communication which is capable of increasing an execution transmission efficiency by en~ering data communication substantially at the same time that a calling mode is established.
3a~
According to the present invention, there is provided method for formatting an answer signal in mobile radio communication, comprising the steps of forming a block of answer signal indicating reception of data transmitted from a transmission side, dividing the block of an~wer signal into a plurality of blocks Of data, adding single predetermined signals indicating a re~ult of reception of data to terminal ends of the blocks of data, respectively, forming a signal block composed of a combination of the blocks of data and the predetermined ~ignal~, modulating the signal block, transmitting the modulated signal block, receiving and demodulating the transmitted signal block, and confirming an answer signal of the modulated signal block and recognizing a block of data.
The above and other objects, feature~ and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which a preferred embodiment of the present invention is shown by way of illustrative example.
BRIEF DESCRIPTION OF THE DRAWINGS
~ig. 1 i~ a block diagram of a mobile radio data communication system;
Fig. 2 iS a diagram showing a transmission control sequence in data communicatlon;
Fig. 3 is a diagram of an answer signal transmission lZ94332 f ormat;
Fig. 4a i~ a block diagram of a data modem in a land ~tation employing a method for formatting an answer signal of the present invention; and Fig. 4b is a block diagram of a data modem in a mobile employing a method for formatting an an~wer ~ignal of the present invention.
DES~RIPTION OF T~E PREFERRED EMBODIMENT
Fig. 1 schematically show~ a mobile radio data communication sy~tem comprl~ing a computer 1, a telephone set 2, a data modem 3, a public circuit 4, a mobile telecommunication ~witching office (MTSO) 5, cell ~ites 6, a mobile 7, an automo~ile telephone transmitter/receiver unit (TRU) 8~ a data modem 9~ a control unit (CU) 10, and a computer 11. The component~ rangin~ from the computer 1 to the cell sites 6 are in a land station, and components ranging from the TRU 8 tO the computer 11 are on the mobile 7.
Data communication between the computer ] in the land ~tation and the computer 11 on the mobile 7 will be described with reference to Fig. 1. While the computer 1 and the telephone ~et 2 are coupled to the data modem 3, the connection between the computer 1 and the data modem 3 becomes effective by switching to a data mode. A block of data i~ sent from the computer 1 to the data modem 3 in which it is encoded by an error-correcting code. The data ~2S~4~32 block i~ then ~ent frorn the data modem 3 to the public circuit 4. The data block i5 then transmitted from the MTSo 5 and a cell site 6 to tlle mobile 7 where it is received by the TRU 8. The received data i~ thereafter decoded by the data modem 9. If the received data is correct data, then it is sent to the computer 11. If the received data contains an error or error~, the data modem g a~ks the land station to resend the ~ame data block.
This process i~ repeated to transmit data from the computer 1 in the land station to the data modem 9 on the mobile 7. Data can be transmitted from the computer 11 on the mobile 7 to the computer 1 in the land station in the same manner as described above. It is also possible to effect telephonic communication between the telephone set 2 and a control unit (hand set) on the mobile 7.
~ A communication sequence using the network shown in Fig. 1 will be de~cribed with reference to Fig. 2.
Fir~t, the telephone set 2 i~ removed from it hook toff hook) by the u~er to call the mobile from the land station. A dial tone requesting dialing signals is heard, and the user dials the directory number of the mobile.
The mobile receive~ a ringing tone and detects a ringer for thereby confirming the call. The land station then hears a ring-back tone from the mobile. Thereafter, the mobile sends an answer signal (answer tone~ which is a single signal to the land station.
Fig. 3 illustrates an answer signal transmission format according to an embodiment of the pre~ent invention. Designated at 1, 3, 5, 7 are single answer signalfi, and 2, 4, 6, 8 are ACK siynals (which may be NAK
~ignal~). In the illu~trated transmission format, the answer ~ignal~ 1, 3, 5, 7 and the A~K signal~ 2, 4, 6, 8 are alternately inserted. However, the an~wer ~ignal~ and the ACK (or NAK) signals may be in~erted in other combinations. The time period from the beginning of the an~wer signal 1 to the terminal end of the ~CK signal 8 i~
substantially the same as the conventional time period.
Therefore, by u~ing the an~wer ~ignal tran~mi~ion format according to the embodiment of the invention, when the called party an~wer~ the call, the calling party establishes a calling mode with the answer signal 1 and immediately receives the next ACK signal 2 in a ~hort period of time to confirm the receipt of the tran~mi~ion.
Thu~, the calling party and the called party can immediately initiate data communication. Even if the ACK
~ignal 2 i~ dropped due to fading, city noi~e, or the like, the second ACK signal 4 can be received, so that the initial proces~ can be effected without fail.
The method for formatting the an~wer ~ignal of the invention is employed in the data modem 3 in the land ~tation and the data modem 9 on the mobile 7. Fig. 4a shows in block form the data modem 3 in the land station, and Fig. 4b show~ in block form the data modem 9 on the mobile. The data modem 3 includes a processor 30], an RS-23ZC interface a~sembly 310, a power source 313, a modemas~ernbly 317, and an ORG signal/ringer detector 326. The computer 1 shown in Fig. 1 is connected to an RS-232C
interface port 342, the telephone set 2 to a TELSET
interface 341, and the public circuit 4 to a TELCO
interface 34~.
Operation to transmit data from the data mod-em 3 in the land station to the mobile 7 will now be described below. When the data modem 3 is energized, an ORG/ANS
logic function unit 325 detect~ whether the data modem 3 is in a transmission mode or a reception mode. It is assumed here that the data modem 3 is in a transmission mode. The transmi~sion mode is sent through a peripheral interface 322 to a CPU 302 in the proces~or 301, and the CPU 302 ackowledges the starting of data transmi~sion.
Then, the CPU 302 checks the RS-232C interface assembly 310 which comprises a driver & receiver 311 and a data communication interface 313 to see if the computer 1 connected to the RS-232C interface port 342 i~ ready or not. Data to be transmitted from the computer 1 i~ read into a RAM 304 in the processor 301 in which it is encoded With an error-correcting code to form a data block. For telephonic communication, ~ince the data modem is connected to telephone ~et 2 via the T~LSET interface 340, a driver 330 is operated to shift a line switch 329 to the TELCO interface 341 for connection to the public circuit 4. The CPU 302 waits for an ACK ~ignal from the mobile 7.
1~94332 The ACK signal is received through the TELCO interface 341, demodulated by the modem assernbly 317, and fed to the processor 301 through the peripheral interface 319. Since the modem assembly 317 is of a known nature, its operation will not be described. When the ACK signal is received, the CPU 302 transmits the block data stored in the RAM 304 to the mobile 7.
As described above, an answer signal transmission format compri~es a combination of answer signal~ and ACK
or NAK signals in the initial process of data communication. Therefore, data communication can be initiated at substantially the same time that a calling mode is established, and the AC~ or NAK signals can reliably be received even when fading or city noise is generated, so that the system can enter a next communication process without fail.
The data block is sent by the CPU 302 from the RAM
304 through the peripheral interface 319, the modem 318, the line switch 329, and the TELCO interface 341 to the public circuit 4, from which the data block is transmitted via the MTSO 5 and the cell site 6 to the mobile 7.
Successive data blocks are similarly encoded with an error-correcting code by the RAM 304 and then transmi~ted.
Reception by the mobile 7 of the transmitted data will be described with reference to Figs. 1 and 4b. The mobile data modem includes a processor 901, an RS-232C
interface assembly 910, a power source 913, and a modem 3.32 a~sembly 917. The computer ].1 shown in Fig. 1 is connected to an RS-232C interface port 942, and the automobile telephone tran~mitter/receiver unit (TRU) 8 and the control unit (CU) 10 are connected to a TRU/CU
interface port 940. A ringing signal tran~mitted from the la.nd station is ~ent to the modem as~embly 917 through the TRU/CU interface port 940 and an audio path switch 932 The received modulated data i~ then demodulated by the modem a~sembly 917 and fed to a CPU 902 in the proces~or 901 via a peripheral interface 9l.9. When the CPu 902 find~ the received data to be a ringing signal, the CPU
. 902 send~ the signal to a RAM 904 and i~sue~ ACK signals a~ shown in Fig. 3. The ACK ~ignal~ are tran~mitted through the modem assembly 917, the audio path ~witch 932, and the TRUlCU interface port 940 to the land ~tation.
Upon con~irming the ACK signals, the land station transmits a block of data which i~ sent through the T~U/CU interface port 940 and the audio path switch 932 to the modem a~sembly 917. The modem assembly 917 demodulate~ the received modulated data block, which i~ ~ent via the peripheral interface 919 to the RAM 904 in the processor 901. The audio path switch 932 effect~ path switching for audio ~ignal~ between a data mode and a conver~ation mode.
The CPU 902 encodes the data which has been stored in the RAM 904. When encoded and properly received, the data i~
fed to the computer 11 through the RS~232C interface assembly 910 and the RS-232C interface port 942.
lZ~33;~
Successive data blocks from the computer 1 in the land station are similarly transmitted to the mobile computer 11. Data transmission from the mobile computer 11 to the land computer 1 is also similarly carried out.
Although a certain preferred embodiment has been shown and described, it should be understood that many changes and modifications may be made therein without departing from the scope of the appended claim.
Claims (8)
1. Method for formatting an answer signal in mobile radio communication, comprising the steps of:
1) forming a block of answer signal indicating reception of data transmitted from a transmission side;
1) forming a block of answer signal indicating reception of data transmitted from a transmission side;
2) dividing said block of answer signal into a plurality of blocks of data;
3) adding single predetermined signals indicating a result of reception of data to terminal ends of said blocks of data, respectively;
4) forming a signal block composed of a combination of said blocks of data and said predetermined signals;
5) modulating said signal block;
6) transmitting the modulated signal block;
7) receiving and demodulating the transmitted signal block; and
8) confirming an answer signal of the modulated signal block and recognizing a block of data.
2. Method for fomrmatting an answer signal in mobile radio communication according to claim 1, wherein an answer signal transmission format is composed of a plurality of said single answer signals indicating reception of data and a plurality of said single predetermined signals indicating a result of reception of data.
3. Method for formatting an answer signal in mobile radio communication according to claim 2, wherein a plurality of said single predetermined signals are composed of ACK signals.
4. Method for formatting an answer signal in mobile radio communication according to claim 2, wherein a plurality of said single predetermined signals are composed of NAK signals.
2. Method for fomrmatting an answer signal in mobile radio communication according to claim 1, wherein an answer signal transmission format is composed of a plurality of said single answer signals indicating reception of data and a plurality of said single predetermined signals indicating a result of reception of data.
3. Method for formatting an answer signal in mobile radio communication according to claim 2, wherein a plurality of said single predetermined signals are composed of ACK signals.
4. Method for formatting an answer signal in mobile radio communication according to claim 2, wherein a plurality of said single predetermined signals are composed of NAK signals.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP234326/1986 | 1986-10-03 | ||
| JP61234326A JPS6390249A (en) | 1986-10-03 | 1986-10-03 | Response signal system in data communication |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1294332C true CA1294332C (en) | 1992-01-14 |
Family
ID=16969250
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000548456A Expired - Fee Related CA1294332C (en) | 1986-10-03 | 1987-10-02 | Method for formatting an answer signal in data transmission |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JPS6390249A (en) |
| CA (1) | CA1294332C (en) |
| GB (1) | GB2197164A (en) |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58201465A (en) * | 1982-05-19 | 1983-11-24 | Ricoh Co Ltd | Facsimile communication system |
| JPS60197095A (en) * | 1984-03-21 | 1985-10-05 | Tamura Electric Works Ltd | Signal transmission system of pushbutton telephone set |
| JPS6143850A (en) * | 1984-08-07 | 1986-03-03 | Nec Corp | Packet continuous transmission system |
| JPH0618358B2 (en) * | 1985-04-09 | 1994-03-09 | 沖電気工業株式会社 | Error control coding system |
| JPS6251326A (en) * | 1985-08-30 | 1987-03-06 | Oki Electric Ind Co Ltd | Retransmission control system in data communication |
-
1986
- 1986-10-03 JP JP61234326A patent/JPS6390249A/en active Granted
-
1987
- 1987-09-30 GB GB08722992A patent/GB2197164A/en not_active Withdrawn
- 1987-10-02 CA CA000548456A patent/CA1294332C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6390249A (en) | 1988-04-21 |
| JPH0548986B2 (en) | 1993-07-23 |
| GB8722992D0 (en) | 1987-11-04 |
| GB2197164A (en) | 1988-05-11 |
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| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |