CA2614573A1 - Variable rate transmission method, transmitter and receiver using the same - Google Patents
Variable rate transmission method, transmitter and receiver using the same Download PDFInfo
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- CA2614573A1 CA2614573A1 CA002614573A CA2614573A CA2614573A1 CA 2614573 A1 CA2614573 A1 CA 2614573A1 CA 002614573 A CA002614573 A CA 002614573A CA 2614573 A CA2614573 A CA 2614573A CA 2614573 A1 CA2614573 A1 CA 2614573A1
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Abstract
A variable rate transmission method that can vary the transmission rate of data. A transmitting side supplies a transmitted data sequence to an error detecting encoder 105 and a frame memory 103.
The frame memory 103 stores data of a variable length to be transmitted in one frame. The error detecting encoder 105 calculates an error detecting code (such as CRC code) for each frame of the transmitted data. A multiplexer 104 adds the calculated error detecting code ahead of the transmitted data to place it at the initial position of the frame, and sequentially outputs the data sequence frame by frame. A receiving side calculates an error detecting code of the data in each transmitted frame in the same manner as the transmitting side, and compares the calculated error detecting code with the error detecting code at the initial position of the frame. The end bit of the frame data is decided as a position at which the two error detecting codes coincide. This makes it possible to transmit variable length data without informing the receiving side of the data length in each frame. This is equivalent that the transmission rate can be varied freely.
The frame memory 103 stores data of a variable length to be transmitted in one frame. The error detecting encoder 105 calculates an error detecting code (such as CRC code) for each frame of the transmitted data. A multiplexer 104 adds the calculated error detecting code ahead of the transmitted data to place it at the initial position of the frame, and sequentially outputs the data sequence frame by frame. A receiving side calculates an error detecting code of the data in each transmitted frame in the same manner as the transmitting side, and compares the calculated error detecting code with the error detecting code at the initial position of the frame. The end bit of the frame data is decided as a position at which the two error detecting codes coincide. This makes it possible to transmit variable length data without informing the receiving side of the data length in each frame. This is equivalent that the transmission rate can be varied freely.
Claims (61)
1. A variable rate transmission method which varies an average transmission rate by transmitting each frame of a fixed duration, said frame holding transmitted data of a variable length, wherein a transmitting side comprises the steps of:
calculating in each frame an error detecting code of said transmitted data;
transmitting said transmitted data and said error detecting code in said each frame at a predetermined fixed transmission rate; and pausing transmission in a blank of each frame, said blank being a part of said frame at which said transmitted data or said error detecting code is absent, and wherein a receiving side comprises the steps of:
receiving said each frame at said fixed transmission rate;
detecting said error detecting code in said each frame; and recovering said transmitted data of the variable length in said each frame in response to a detecting result of said error detecting code.
calculating in each frame an error detecting code of said transmitted data;
transmitting said transmitted data and said error detecting code in said each frame at a predetermined fixed transmission rate; and pausing transmission in a blank of each frame, said blank being a part of said frame at which said transmitted data or said error detecting code is absent, and wherein a receiving side comprises the steps of:
receiving said each frame at said fixed transmission rate;
detecting said error detecting code in said each frame; and recovering said transmitted data of the variable length in said each frame in response to a detecting result of said error detecting code.
2. The variable rate transmission method as claimed in claim 1, wherein said step of detecting said error detecting code sequentially divides received data in said each frame by predetermined data while shifting said received data bit by bit, and decides that said error detecting code is detected at a point at which said received data can be divided.
3. The variable rate transmission method as claimed in claim 2, wherein said step of recovering said transmitted data decides an end bit position of said transmitted data at a point preceding the point at which said error detecting code is detected by the number of bits of said error detecting code.
4. The variable rate transmission method as claimed in claim 1, wherein said transmitting side further comprises the steps of:
periodically inserting pilot symbols of a known pattern into said each frame; and disposing important data of said transmitted data near said pilot symbols, and wherein said receiving side comprises the steps of:
detecting said pilot symbols;
compensating said transmitted data and said error detecting code which are received using said pilot symbols which are detected; andrelocating said transmitted data to its original order.
periodically inserting pilot symbols of a known pattern into said each frame; and disposing important data of said transmitted data near said pilot symbols, and wherein said receiving side comprises the steps of:
detecting said pilot symbols;
compensating said transmitted data and said error detecting code which are received using said pilot symbols which are detected; andrelocating said transmitted data to its original order.
5. The variable rate transmission method as claimed in claim 4, wherein said step of disposing said important data near said pilot symbols comprises the steps of:
writing said transmitted data row by row into a memory with N rows and M columns alternately from a top row and a bottom row of said memory, where N and M are positive integers;
reading from said memory, column by column, said transmitted data which has been stored in said memory;
inserting said pilot symbols each time said column is read, and wherein said important data is placed in advance at an initial position of said transmitted data.
writing said transmitted data row by row into a memory with N rows and M columns alternately from a top row and a bottom row of said memory, where N and M are positive integers;
reading from said memory, column by column, said transmitted data which has been stored in said memory;
inserting said pilot symbols each time said column is read, and wherein said important data is placed in advance at an initial position of said transmitted data.
6. The variable rate transmission method as claimed in claim 4, wherein said method is CDMA (Code Division Multiple Access), in which said transmitting side comprises the steps of performing primary modulation of said transmitted data and said error detecting code, and performing secondary modulation of a signal which has undergone said primary modulation using a spreading code sequence.
7. The variable rate transmission method as claimed in claim 6, wherein transmission power of said pilot symbols and said important data is increased.
8. The variable rate transmission method as claimed in claim 1, wherein said transmitting side comprises the steps of:
informing said receiving side that said transmitted data and said error detecting code are repeated K times, where K is a positive integer, when a total amount of said transmitted data and said error detecting code is equal to or less than 1/K of a maximum amount of data that can be transmitted by one frame;
generating frames, in each of which each bit of said transmitted data and said error detecting code is repeated K times; and transmitting said frames which have been generated, at transmission power of 1/K of transmission power used when said each bit is not repeated, and wherein said receiving side comprises the step of:
recovering original data from said transmitted data and said error detecting code by thinning out data using said K informed from said transmitted side.
informing said receiving side that said transmitted data and said error detecting code are repeated K times, where K is a positive integer, when a total amount of said transmitted data and said error detecting code is equal to or less than 1/K of a maximum amount of data that can be transmitted by one frame;
generating frames, in each of which each bit of said transmitted data and said error detecting code is repeated K times; and transmitting said frames which have been generated, at transmission power of 1/K of transmission power used when said each bit is not repeated, and wherein said receiving side comprises the step of:
recovering original data from said transmitted data and said error detecting code by thinning out data using said K informed from said transmitted side.
9. The variable rate transmission method as claimed in claim 8, wherein said transmitting side comprises the steps of:
periodically inserting pilot symbols of a known pattern into said each frame; and disposing important data of said transmitted data near said pilot symbols in said each frame, and wherein said receiving side comprises the steps of:
detecting said pilot symbols;
compensating said transmitted data and said error detecting code which have been received using said pilot symbols detected; and relocating said transmitted data received to its original order.
periodically inserting pilot symbols of a known pattern into said each frame; and disposing important data of said transmitted data near said pilot symbols in said each frame, and wherein said receiving side comprises the steps of:
detecting said pilot symbols;
compensating said transmitted data and said error detecting code which have been received using said pilot symbols detected; and relocating said transmitted data received to its original order.
10. The variable rate transmission method as claimed in claim 1, wherein said transmitting side comprises the steps of:
allocating each frame of a plurality of channels with said transmitted data;
periodically inserting pilot symbols of a known pattern into each frame of one of said plurality of channels;
disposing important data of said transmitted data near said pilot symbols; and spreading said transmitted data simultaneously using different spreading code sequences assigned to said plurality of channels to transmit spread data through said each channel, and wherein said receiving side comprises the steps of:
simultaneously receiving said plurality of channels;
detecting pilot symbols of said one of said plurality of channels;
compensating received signals of said plurality of channels using pilot symbols detected; and relocating said transmitted data received to its original order.
allocating each frame of a plurality of channels with said transmitted data;
periodically inserting pilot symbols of a known pattern into each frame of one of said plurality of channels;
disposing important data of said transmitted data near said pilot symbols; and spreading said transmitted data simultaneously using different spreading code sequences assigned to said plurality of channels to transmit spread data through said each channel, and wherein said receiving side comprises the steps of:
simultaneously receiving said plurality of channels;
detecting pilot symbols of said one of said plurality of channels;
compensating received signals of said plurality of channels using pilot symbols detected; and relocating said transmitted data received to its original order.
11. The variable rate transmission method as claimed in claim 10, wherein data of said plurality of channels are transmitted with a phase of a carrier of each of said plurality of channels being shifted.
12. The variable rate transmission method as claimed in any one of claims 1-7, 9 and 11, wherein said important data is control data.
13. The variable rate transmission method as claimed in claim 1, wherein said transmitting side comprises the step of disposing said error detecting code at a fixed position in said each frame, and said receiving side comprises the steps of extracting said error detecting code placed at said fixed position in said each frame, and obtaining the number of bits of said transmitted data on the basis of said error detecting code.
14. The variable rate transmission method as claimed in claim 13, wherein said method is a CDMA
data transmission method in which said transmitting side comprises the steps of performing primary modulation of said transmitted data and said error detecting code in said each frame, and performing secondary modulation of primary modulated data in each frame by using a spreading code sequence, to be transmitted.
data transmission method in which said transmitting side comprises the steps of performing primary modulation of said transmitted data and said error detecting code in said each frame, and performing secondary modulation of primary modulated data in each frame by using a spreading code sequence, to be transmitted.
15. The variable rate transmission method as claimed in claim 14, wherein said transmitting side comprises the step of performing error correcting encoding and interleaving of said transmitted data before said primary modulation, and wherein said receiving side comprises the steps of performing a primary demodulation of said transmitted data which is received, and performing deinterleaving and error correcting decoding of said transmitted data which have undergone said primary demodulation.
16. The variable rate transmission method as claimed in claim 13, wherein said transmitting side comprises the steps of:
repeating each bit of said transmitted data and said error detecting code K times, where K is a positive integer, when a total amount of said transmitted data and said error detecting code in said each frame is equal to or less than 1/K of a maximum amount of data that can be transmitted by said each frame;
reducing transmission power of said each frame to 1/K of transmission power used when said bit is not repeated;
and wherein said receiving side comprises the step of:
integrating over K bit interval said transmitted data and said error detecting code which have been received; and recovering said transmitted data by performing thinning out processing of integrated data for every K bits.
repeating each bit of said transmitted data and said error detecting code K times, where K is a positive integer, when a total amount of said transmitted data and said error detecting code in said each frame is equal to or less than 1/K of a maximum amount of data that can be transmitted by said each frame;
reducing transmission power of said each frame to 1/K of transmission power used when said bit is not repeated;
and wherein said receiving side comprises the step of:
integrating over K bit interval said transmitted data and said error detecting code which have been received; and recovering said transmitted data by performing thinning out processing of integrated data for every K bits.
17. The variable rate transmission method as claimed in claim 1, wherein said transmitting side comprises the step of:
adding to a fixed position in said each frame, transmission rate information representative of the number of bits of data in said each frame and said error detecting code, and wherein said receiving side comprises the steps of:
obtaining an end bit position of said transmitted data in each said frame in response to said transmission rate information;
calculating error detecting code of said transmitted data to said end position;
comparing said calculated error detecting code with said error detecting code which has been received; and deciding that said transmitted data to said end bit position is correct when a compared result of the step of comparing coincides.
adding to a fixed position in said each frame, transmission rate information representative of the number of bits of data in said each frame and said error detecting code, and wherein said receiving side comprises the steps of:
obtaining an end bit position of said transmitted data in each said frame in response to said transmission rate information;
calculating error detecting code of said transmitted data to said end position;
comparing said calculated error detecting code with said error detecting code which has been received; and deciding that said transmitted data to said end bit position is correct when a compared result of the step of comparing coincides.
18. The variable rate transmission method as claimed in claim 17, wherein transmission method is a CDMA data transmission method in which said transmitting side comprises the steps of performing primary modulation of said transmitted data and said error detecting code in said each frame, and performing secondary modulation of primary modulated data in each frame by using a spreading code sequence, to be transmitted.
19. The variable rate transmission method as claimed in claim 18, wherein said transmitting side comprises the steps of:
performing error correcting encoding of said transmitted data, said transmission rate information and said error detecting code in said each frame before said primary modulation, and interleaving error correcting encoded data in said each frame, followed by supplying interleaved data to said step of performing primary modulation, and wherein said receiving side comprises the steps of:
despreading data in said each frame which is received by using a spreading code sequence;
performing a primary demodulation of a despread signal;
deinterleaving transmission data which has undergone said primary demodulation;
performing error correcting decoding of said transmission rate information and said error detecting code; and performing error correcting decoding of said transmitted data to its end bit in accordance with a result of said error correcting decoding of the preceding step.
performing error correcting encoding of said transmitted data, said transmission rate information and said error detecting code in said each frame before said primary modulation, and interleaving error correcting encoded data in said each frame, followed by supplying interleaved data to said step of performing primary modulation, and wherein said receiving side comprises the steps of:
despreading data in said each frame which is received by using a spreading code sequence;
performing a primary demodulation of a despread signal;
deinterleaving transmission data which has undergone said primary demodulation;
performing error correcting decoding of said transmission rate information and said error detecting code; and performing error correcting decoding of said transmitted data to its end bit in accordance with a result of said error correcting decoding of the preceding step.
20. The variable rate transmission method as claimed in claim 17, wherein said transmitting side comprises the step of:
placing said transmission rate information associated with a current frame at a fixed position in a preceding frame, and wherein said receiving side comprises the steps of:
extracting said transmission rate information received in said preceding frame; and deciding an end bit position of data in said current frame in response to said transmission rate information which has been extracted.
placing said transmission rate information associated with a current frame at a fixed position in a preceding frame, and wherein said receiving side comprises the steps of:
extracting said transmission rate information received in said preceding frame; and deciding an end bit position of data in said current frame in response to said transmission rate information which has been extracted.
21. The variable rate transmission method as claimed in claim 20, wherein said transmitting side comprises the steps of:
performing error correcting encoding of data in said each frame;
interleaving said each frame;
performing primary modulation of said each frame which has been interleaved; and performing secondary modulation of primary modulated transmission data in said each frame by using a spreading code sequence, and wherein said receiving side comprises the steps of:
performing a primary demodulation of said transmission data which has been received;
deinterleaving said transmission data which has undergone said primary demodulation;
performing error correcting decoding of said transmission rate information which has been transmitted in said preceding frame, and of said error detection code in said current frame; and performing error correcting decoding said transmitted data to its end bit in accordance with a result of said error correcting decoding of the preceding step.
performing error correcting encoding of data in said each frame;
interleaving said each frame;
performing primary modulation of said each frame which has been interleaved; and performing secondary modulation of primary modulated transmission data in said each frame by using a spreading code sequence, and wherein said receiving side comprises the steps of:
performing a primary demodulation of said transmission data which has been received;
deinterleaving said transmission data which has undergone said primary demodulation;
performing error correcting decoding of said transmission rate information which has been transmitted in said preceding frame, and of said error detection code in said current frame; and performing error correcting decoding said transmitted data to its end bit in accordance with a result of said error correcting decoding of the preceding step.
22. The variable rate transmission method as claimed in any one of claims 17-21, wherein said transmission method comprises, when the number of bits of said transmitted data in said each frame is equal to or less than 1/K of the maximum number of bits of data that can be transmitted by said each frame, where K is a positive integer, at said transmitting side:
repeating each bit of said transmitted data K
times, where K is a positive integer; and reducing transmission power of said each frame to 1/K of transmission power used when said bit is not repeated, and at said receiving side:
integrating over a K bit interval said transmitted data which has been received; and recovering said transmitted data by performing thinning out processing of integrated data for every K bits.
repeating each bit of said transmitted data K
times, where K is a positive integer; and reducing transmission power of said each frame to 1/K of transmission power used when said bit is not repeated, and at said receiving side:
integrating over a K bit interval said transmitted data which has been received; and recovering said transmitted data by performing thinning out processing of integrated data for every K bits.
23. A transmitter which varies an average transmission rate by transmitting each frame of a fixed duration, said frame holding transmitted data of a variable length, said transmitter comprising:
means for calculating in said each frame an error detecting code of said transmitted data; and means for transmitting said transmitted data and said error detecting code in said each frame at a predetermined fixed transmission rate, and for pausing transmission in a blank of each frame, said blank being a part of said frame at which said transmitted data or said error detecting code is absent.
means for calculating in said each frame an error detecting code of said transmitted data; and means for transmitting said transmitted data and said error detecting code in said each frame at a predetermined fixed transmission rate, and for pausing transmission in a blank of each frame, said blank being a part of said frame at which said transmitted data or said error detecting code is absent.
24. The transmitter as claimed in claim 23, further comprising:
pilot symbol inserting means for periodically inserting pilot symbols of a known pattern into said each frame;
a memory for storing said transmitted data; and data relocating means for disposing near said pilot symbols important data of said transmitted data stored in said memory.
pilot symbol inserting means for periodically inserting pilot symbols of a known pattern into said each frame;
a memory for storing said transmitted data; and data relocating means for disposing near said pilot symbols important data of said transmitted data stored in said memory.
25. The transmitter as claimed in claim 24, wherein said data relocating means disposes said important data near said pilot symbols by writing said transmitted data into said memory row by row with a length of M bits, and by reading said stored transmitted data from said memory column by column with a length of N bits, wherein N is the number of bits of a slot sandwiched by said pilot symbols, and M is the number of said slots contained in said each frame.
26. The transmitter as claimed in claim 25, wherein said data relocating means writes said important data into said memory alternately from a top row and a bottom row of said memory.
27. The transmitter as claimed in any one of claims 24-26, further comprising:
a primary modulator for modulating data in said each frame including said transmitted data, and a secondary modulator for performing secondary modulation that spreads data of said each frame which has undergone said primary modulation using a spreading code sequence, and wherein said pilot symbol inserting means is connected between said primary modulator and said secondary modulator, and periodically inserts said pilot symbols between said slots.
a primary modulator for modulating data in said each frame including said transmitted data, and a secondary modulator for performing secondary modulation that spreads data of said each frame which has undergone said primary modulation using a spreading code sequence, and wherein said pilot symbol inserting means is connected between said primary modulator and said secondary modulator, and periodically inserts said pilot symbols between said slots.
28. The transmitter as claimed in claim 26, further comprising a transmission power control means connected to said pilot symbol inserting means for controlling transmission power of data in said each frame in accordance with a degree of importance of said data.
29. The transmitter as claimed in claim 28, wherein a predetermined particular code is written in a blank in said each frame, said blank occurring when the number of bits of said transmitted data is less than the maximum number of bits of said each frame, and wherein said transmission power control means reduces transmission power of said blank to zero.
30. The transmitter as claimed in claim 29, further comprising a repeater preceding said memory for repeating said transmitted data and said error detecting code K times for each bit, and wherein said transmission power control means reduces transmission power of said each frame to 1/K as compared with transmission power used when said K
time repeating is not performed.
time repeating is not performed.
31. The transmitter as claimed in claim 23, further comprising:
pilot symbol inserting means for periodically inserting pilot symbols of a known pattern into said each frame;
a memory for storing said transmitted data, said memory capable of reading multiple sets of transmitted data associated with a plurality of channels;
data relocating means for writing data into said memory such that important data of said transmitted data stored in said memory is placed near said pilot symbols;
a plurality of primary modulators for primary modulating said multiple sets of transmitted data read from said memory;
a plurality of transmission power control means for controlling transmission power of said each frame output from said primary modulators;
a plurality of secondary modulators for spreading data in said each frame output from said transmission power control means by using different spreading code sequences; and an adder for adding multiple signals output from said secondary modulators, and wherein said data relocating means divides said transmitted data to be written into said memory, simultaneously reads from said memory said multiple sets of transmitted data which have been formed by the dividing, and supplies read data to said plurality of primary modulators, and said pilot symbol inserting means is connected after one of said plurality of primary modulators for periodically inserting said pilot symbols, and said plurality of transmission power control means increase transmission power while transmitting said important data.
pilot symbol inserting means for periodically inserting pilot symbols of a known pattern into said each frame;
a memory for storing said transmitted data, said memory capable of reading multiple sets of transmitted data associated with a plurality of channels;
data relocating means for writing data into said memory such that important data of said transmitted data stored in said memory is placed near said pilot symbols;
a plurality of primary modulators for primary modulating said multiple sets of transmitted data read from said memory;
a plurality of transmission power control means for controlling transmission power of said each frame output from said primary modulators;
a plurality of secondary modulators for spreading data in said each frame output from said transmission power control means by using different spreading code sequences; and an adder for adding multiple signals output from said secondary modulators, and wherein said data relocating means divides said transmitted data to be written into said memory, simultaneously reads from said memory said multiple sets of transmitted data which have been formed by the dividing, and supplies read data to said plurality of primary modulators, and said pilot symbol inserting means is connected after one of said plurality of primary modulators for periodically inserting said pilot symbols, and said plurality of transmission power control means increase transmission power while transmitting said important data.
32. The transmitter as claimed in claim 31, further comprising a plurality of phase controllers each connected after said plurality of primary modulators for shifting phases of carriers of said secondary modulators.
33. The transmitter as claimed in claim 23, further comprising means for adding said error detecting code to a fixed position in said each frame.
34. The transmitter as claimed in claim 33, further comprising:
means for performing error correcting encoding of data in said each frame;
means for interleaving data which has undergone said error correcting encoding;
means for primary modulating interleaved data;
and means for secondary modulating primary modulated data by using a spreading code.
means for performing error correcting encoding of data in said each frame;
means for interleaving data which has undergone said error correcting encoding;
means for primary modulating interleaved data;
and means for secondary modulating primary modulated data by using a spreading code.
35. The transmitter as claimed in claim 33 or 34, further comprising:
means for repeating K times each bit of data in said each frame when the number of bits of said data in said each frame is equal to or less than 1/K of the maximum number of bits that can be transmitted in one frame, where K is a positive integer; and transmission power control means for reducing transmission power of said each frame to 1/K in comparison with transmission power used when said K
time repeating is not performed.
means for repeating K times each bit of data in said each frame when the number of bits of said data in said each frame is equal to or less than 1/K of the maximum number of bits that can be transmitted in one frame, where K is a positive integer; and transmission power control means for reducing transmission power of said each frame to 1/K in comparison with transmission power used when said K
time repeating is not performed.
36. The transmitter as claimed in claim 23, further comprising adding means for adding, to a fixed position of said each frame, transmission rate information representative of the total number of data in said each frame, and said error detecting code.
37. The transmitter as claimed in claim 36, further comprising:
means for performing error correcting encoding of said transmitted data, said transmission rate information, and said error detecting code in said each frame;
means for interleaving data which has undergone said error correcting encoding;
means for primary modulating interleaved data;
and means for secondary modulating primary modulated data by using a spreading code.
means for performing error correcting encoding of said transmitted data, said transmission rate information, and said error detecting code in said each frame;
means for interleaving data which has undergone said error correcting encoding;
means for primary modulating interleaved data;
and means for secondary modulating primary modulated data by using a spreading code.
38. The transmitter as claimed in claim 36, further comprising means for adding said transmission rate information associated with a current frame to a fixed position in a preceding frame.
39. The transmitter as claimed in claim 38, further comprising:
means for performing error correcting encoding of said transmitted data, said transmission rate information, and said error detecting code in said each frame;
means for interleaving data which has undergone said error correcting encoding;
means for primary modulating interleaved data;
and means for secondary modulating primary modulated data by using a spreading code.
means for performing error correcting encoding of said transmitted data, said transmission rate information, and said error detecting code in said each frame;
means for interleaving data which has undergone said error correcting encoding;
means for primary modulating interleaved data;
and means for secondary modulating primary modulated data by using a spreading code.
40. The transmitter as claimed in any one of claims 36-39, further comprising:
means for repeating K times each bit of data in said each frame when the number of bits of said data in said each frame is equal to or less than 1/K of the maximum number of bits that can be transmitted in one frame, where K is a positive integer; and transmission power control means for reducing transmission power of said each frame to 1/K in comparison with transmission power used when said K
time repeating is not performed.
means for repeating K times each bit of data in said each frame when the number of bits of said data in said each frame is equal to or less than 1/K of the maximum number of bits that can be transmitted in one frame, where K is a positive integer; and transmission power control means for reducing transmission power of said each frame to 1/K in comparison with transmission power used when said K
time repeating is not performed.
41. A receiver comprising:
means for receiving, at a fixed transmission rate, frames each including transmitted data and an error correcting code;
means for detecting error detecting code in said each frame; and means for recovering said transmitted data of a variable length in said each frame in response to a detection result of said error detecting code.
means for receiving, at a fixed transmission rate, frames each including transmitted data and an error correcting code;
means for detecting error detecting code in said each frame; and means for recovering said transmitted data of a variable length in said each frame in response to a detection result of said error detecting code.
42. The receiver as claimed in claim 41, wherein means for detecting said error detecting code sequentially divides received data in each said frame by predetermined data while shifting said received data bit by bit, and decides that said error detecting code is detected at a point at which said received data can be divided.
43. The receiver as claimed in claim 41, further comprising:
means for detecting pilot symbols of a known pattern, which are inserted into said each frame periodically to be transmitted;
a memory for storing data in said each frame;
and data relocating means for rearranging data written in said memory to an original order when receiving said data in said each frame, in which important data of said transmitted data is disposed near said pilot symbols.
means for detecting pilot symbols of a known pattern, which are inserted into said each frame periodically to be transmitted;
a memory for storing data in said each frame;
and data relocating means for rearranging data written in said memory to an original order when receiving said data in said each frame, in which important data of said transmitted data is disposed near said pilot symbols.
44. The receiver as claimed in claim 43, wherein said data relocating means rearranges said data in said each frame into the original order by writing said data in said each frame into said memory column by column with a length of N bits, and by reading said stored data of said each frame from said memory row by row with a length of M bits, wherein N is the number of bits of a slot sandwiched by said pilot symbols, and M is the number of said slots contained in said each frame.
45. The receiver as claimed in claim 44, wherein said data relocating means carries out reading of said memory alternately from a top row and a bottom row of said memory.
46. The receiver as claimed in any one of claims 43-45, further comprising:
a secondary demodulator for despreading received data by using a spreading code sequence;
a compensator for compensating said data in said each frame by using said pilot symbols; and a primary demodulator for demodulating said data which has been compensated by said compensator.
a secondary demodulator for despreading received data by using a spreading code sequence;
a compensator for compensating said data in said each frame by using said pilot symbols; and a primary demodulator for demodulating said data which has been compensated by said compensator.
47. The receiver as claimed in claim 46, further comprising:
means for integrating over K bit interval said data in said each frame which has been received; and means for recovering said transmitted data by performing thinning out of the integrated data at every K bits.
means for integrating over K bit interval said data in said each frame which has been received; and means for recovering said transmitted data by performing thinning out of the integrated data at every K bits.
48. The receiver as claimed in claim 41, further comprising:
a plurality of secondary demodulators for despreading each of multiple series of frames simultaneously transmitted through a plurality of channels;
a compensator for compensating data in said multiple series of frames by using pilot symbols which are periodically inserted into one of multiple series of frames, and are sent through one of said plurality of channels;
a plurality of primary demodulators for demodulating compensated data;
a memory for storing said multiple series of data at the same time; and data relocating means for rearranging important data disposed near said pilot symbols to its original order by simultaneously writing said multiple series of frames in separated areas of said memory, and by reading written data in an order different from that of writing.
a plurality of secondary demodulators for despreading each of multiple series of frames simultaneously transmitted through a plurality of channels;
a compensator for compensating data in said multiple series of frames by using pilot symbols which are periodically inserted into one of multiple series of frames, and are sent through one of said plurality of channels;
a plurality of primary demodulators for demodulating compensated data;
a memory for storing said multiple series of data at the same time; and data relocating means for rearranging important data disposed near said pilot symbols to its original order by simultaneously writing said multiple series of frames in separated areas of said memory, and by reading written data in an order different from that of writing.
49. The receiver as claimed in claim 48, further comprising phase controllers each provided for each one of said channels for correcting phases of said multiple series of data.
50. The receiver as claimed in claim 41, further comprising:
a secondary demodulator for despreading a received spread signal, and for outputting a despread signal;
a primary demodulator for recovering data in said each frame from said despread signal;
an error detecting code memory for storing said error detecting code placed at a fixed position in said each frame;
means for calculating an error detecting code from said data in said each frame; and comparing means for comparing said calculated error detecting code with said error detecting code stored in said error detecting code memory, wherein data is received of a variable bits in said each frame by obtaining the number of bits of said data in said each frame in response to a result of the comparison.
a secondary demodulator for despreading a received spread signal, and for outputting a despread signal;
a primary demodulator for recovering data in said each frame from said despread signal;
an error detecting code memory for storing said error detecting code placed at a fixed position in said each frame;
means for calculating an error detecting code from said data in said each frame; and comparing means for comparing said calculated error detecting code with said error detecting code stored in said error detecting code memory, wherein data is received of a variable bits in said each frame by obtaining the number of bits of said data in said each frame in response to a result of the comparison.
51. The receiver as claimed in claim 50, further comprising:
means for deinterleaving data output from said primary demodulator; and means for performing error correcting decoding of the data which has been deinterleaved.
means for deinterleaving data output from said primary demodulator; and means for performing error correcting decoding of the data which has been deinterleaved.
52. The receiver as claimed in any one of claims 50 or 51, further comprising:
means for integrating over a K bit interval said data in said each frame which has been received; and means for recovering said transmitted data by performing thinning out of the integrated data at every K bits.
means for integrating over a K bit interval said data in said each frame which has been received; and means for recovering said transmitted data by performing thinning out of the integrated data at every K bits.
53. The receiver as claimed in claim 41, further comprising:
means for obtaining an end bit position of said transmitted data in each said frame which has been received, in response to said transmission rate information which is placed at a fixed position of said each frame to represent the number of bits of said transmitted data in said each frame;
means for calculating error detecting code of said transmitted data to said end position;
means for comparing the calculated error detecting code with said error detecting code which has been transmitted in said each frame; and means for deciding that said transmitted data to said end bit position is correct transmitted data in said each frame when a compared result coincides.
means for obtaining an end bit position of said transmitted data in each said frame which has been received, in response to said transmission rate information which is placed at a fixed position of said each frame to represent the number of bits of said transmitted data in said each frame;
means for calculating error detecting code of said transmitted data to said end position;
means for comparing the calculated error detecting code with said error detecting code which has been transmitted in said each frame; and means for deciding that said transmitted data to said end bit position is correct transmitted data in said each frame when a compared result coincides.
54. The receiver as claimed in claim 53, further comprising:
a secondary demodulator for despreading a received spread signal, and outputs a despread signal;
a primary demodulator for recovering data in said each frame from said despread signal;
means for deinterleaving data output from said primary demodulator;
means for performing error correcting decoding of said transmission rate information and said error detecting code among data output from said means for deinterleaving; and means for performing error correcting decoding of said transmitted data to its end bit position in response to a result of said error correcting decoding.
a secondary demodulator for despreading a received spread signal, and outputs a despread signal;
a primary demodulator for recovering data in said each frame from said despread signal;
means for deinterleaving data output from said primary demodulator;
means for performing error correcting decoding of said transmission rate information and said error detecting code among data output from said means for deinterleaving; and means for performing error correcting decoding of said transmitted data to its end bit position in response to a result of said error correcting decoding.
55. The receiver as claimed in claim 53, wherein said means for deciding determines the end bit position of said transmitted data in a current frame in accordance with said transmission rate information received in a preceding frame.
56. The receiver as claimed in claim 55, further comprising:
a secondary demodulator for despreading a received spread signal, and outputs a despread signal;
a primary demodulator for recovering data in said each frame from said despread signal;
means for deinterleaving data output from said primary demodulator;
means for performing error correcting decoding of said transmission rate information and said error detecting code among data output from said means for deinterleaving; and means for performing error correcting decoding of said transmitted data to its end bit position in response to a result of said error correcting decoding of said transmission rate information received in a preceding frame.
a secondary demodulator for despreading a received spread signal, and outputs a despread signal;
a primary demodulator for recovering data in said each frame from said despread signal;
means for deinterleaving data output from said primary demodulator;
means for performing error correcting decoding of said transmission rate information and said error detecting code among data output from said means for deinterleaving; and means for performing error correcting decoding of said transmitted data to its end bit position in response to a result of said error correcting decoding of said transmission rate information received in a preceding frame.
57. The receiver as claimed in any one of claims 53-56, further comprising, when the number of bits of data in said each frame is equal to or less than 1/K of a maximum number of bits that can be transmitted by one frame, where K is a positive integer:
means for integrating over a K bit interval said data in said each frame which has been received; and means for recovering said transmitted data by performing thinning out of the integrated data at every K bits.
means for integrating over a K bit interval said data in said each frame which has been received; and means for recovering said transmitted data by performing thinning out of the integrated data at every K bits.
58. A variable rate transmission method comprising the steps of:
inserting pilot symbols of a known pattern into each frame periodically, and disposing important data of transmitted data near said pilot symbols, at a transmitting side, and detecting said pilot symbols, compensating by the detected pilot symbols said transmitted data and error detecting code which have been received, and rearranging said transmitted data which has been received to its original order.
inserting pilot symbols of a known pattern into each frame periodically, and disposing important data of transmitted data near said pilot symbols, at a transmitting side, and detecting said pilot symbols, compensating by the detected pilot symbols said transmitted data and error detecting code which have been received, and rearranging said transmitted data which has been received to its original order.
59. The variable rate transmission method as claimed in claim 58, wherein said step of disposing said important data near said pilot symbols comprises the steps of:
writing said transmitted data row by row into a memory with N rows and M columns alternately from a top row and a bottom row of said memory;
reading from said memory, column by column, said transmitted data which has been stored in said memory;
inserting said pilot symbols each time said column is read, and wherein said important data is placed in advance at an initial position of said transmitted data.
writing said transmitted data row by row into a memory with N rows and M columns alternately from a top row and a bottom row of said memory;
reading from said memory, column by column, said transmitted data which has been stored in said memory;
inserting said pilot symbols each time said column is read, and wherein said important data is placed in advance at an initial position of said transmitted data.
60. The variable rate transmission method as claimed in claim 58, wherein said method is a CDMA
data transmission method in which said transmitting side comprises the steps of performing primary modulation of said transmitted data and said error detecting code in said each frame, and performing secondary modulation of primary modulated data in each frame by using a spreading code sequence.
data transmission method in which said transmitting side comprises the steps of performing primary modulation of said transmitted data and said error detecting code in said each frame, and performing secondary modulation of primary modulated data in each frame by using a spreading code sequence.
61. The variable rate transmission method as claimed in claim 60, wherein transmission power of said pilot symbols and said important data are increased.
Applications Claiming Priority (7)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JPJP035,702/1995 | 1995-02-23 | ||
| JP3570295 | 1995-02-23 | ||
| JPJP147,728/1995 | 1995-06-14 | ||
| JP14772895 | 1995-06-14 | ||
| JP32482395 | 1995-12-13 | ||
| JPJP324,823/1995 | 1995-12-13 | ||
| CA002423925A CA2423925C (en) | 1995-02-23 | 1996-02-23 | Variable rate transmission method, transmitter and receiver using the same |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002423925A Division CA2423925C (en) | 1995-02-23 | 1996-02-23 | Variable rate transmission method, transmitter and receiver using the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2614573A1 true CA2614573A1 (en) | 1996-08-29 |
| CA2614573C CA2614573C (en) | 2012-05-01 |
Family
ID=39190487
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2614573A Expired - Lifetime CA2614573C (en) | 1995-02-23 | 1996-02-23 | Variable rate transmission method, transmitter and receiver using the same |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2614573C (en) |
-
1996
- 1996-02-23 CA CA2614573A patent/CA2614573C/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| CA2614573C (en) | 2012-05-01 |
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| Date | Code | Title | Description |
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| EEER | Examination request | ||
| MKEX | Expiry |
Effective date: 20160223 |