Spread spectrum communication apparatus

• US 5,949,816 A
• Filed: 03/05/1997
• Issued: 09/07/1999
• Est. Priority Date: 03/05/1996
• Status: Expired due to Fees

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Okamoto, Naoki
• Primary Examiner(s): Pham, Chi H.
• Assistant Examiner(s): WEBSTER, BRYAN E
• Application Number:
  US08/812,135
• Time in Patent Office: 916 Days
• Field of Search: 375/200, 375/208, 375/259, 375/316, 375/343, 375/347, 375/222, 370/334, 370/491, 455/101
• US Class Current: 375/150
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04B 1/7097 Interference-related aspects
• CPC Class Codes: H04B 1/7107 Subtractive interference cancellation
• CPC Class Codes: H04B 7/2628 using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA] H04B7/2618 takes precedence
• CPC Class Codes: H04J 13/00 Code division multiplex systems for frequency hopping H04B1/713

Abstract

Correlation between a received signal and a PN code is obtained by a correlating portion. A correlation timing signal is detected by a correlation timing detecting portion, a delay profile is calculated by a delay profile calculating portion with reference to the correlation timing signal and a signal from a known data portion detecting portion. The delay profile is applied to a demodulating portion, and setting of path diversity is determined based on the delay profile.

Claims

1. A spread spectrum communication apparatus for transmission/reception using spread spectrum communication in such a data format that has a known data portion at a preamble portion, comprising:

correlating means for correlating a reception signal with a predetermined code;

detecting means for detecting the known data portion from the signal correlated by said correlating means;

known data portion output means for outputting in advance, a correlated output of the known data portion;

modulating/demodulating means for not performing multiplexing at the known data portion output from said known data portion output means and a subsequent specific data portion, and for multiplexing by delaying and combining data at a subsequent specific portion; and

means for calculating a delay profile for outputting a correlated signal at an actual measurement of the known data portion based on a detection signal from said detecting means and comparing the output correlated signal and a correlated output from said known data portion output means to provide a delay profile indicating a state of a delayed signal,

said modulating/demodulating means determining a number of multiplexing and an amount of delay based on the delay profile calculated by said delay profile calculating means.

2. A spread spectrum communication apparatus for transmission/reception using spread spectrum communication in such a data format that has a known data portion at a preamble portion, comprising:

correlating means for correlating a reception signal with a predetermined code;

detecting means for detecting the known data portion from the signal correlated by said correlating means;

known data portion output means for outputting in advance, a correlated output of the known data portion;

modulating/demodulating means for not performing multiplexing at the known data portion output from said known data portion output means and a subsequent specific data portion, and for multiplexing by delaying and combining data at a subsequent specific portion; and

error rate detecting means for detecting an error rate from a demodulated output of said modulating/demodulating means,

said modulating/demodulating means determining a number of multiplexing and an amount of delay based on the error rate detected by said error rate detecting means.

3. A spread spectrum communication apparatus for transmission/reception using spread spectrum communication in such a data format that has a known data portion at a preamble portion, comprising:

correlating means for correlating a reception signal with a predetermined code;

detecting means for detecting the known data portion from the signal correlated by said correlating means;

known data portion output means for outputting in advance, a correlated output of the known data portion;

modulating/demodulating means for not performing multiplexing at the known data portion output from said known data portion output means and a subsequent specific data portion, and for multiplexing by delaying and combining data at a subsequent specific portion; and

carrier to noise ratio detecting means for detecting a carrier to noise ratio from an output of said correlating means,

said modulating/demodulating means determining a number of multiplexing and an amount of delay based on the carrier to noise ratio detected by said carrier to noise ratio detecting means.

4. A spread spectrum communication apparatus for transmission/reception using spread spectrum communication in such a data format that has a known data portion at a preamble portion, comprising:

correlating means for correlating a reception signal with a predetermined code;

detecting means for detecting the known data portion from the signal correlated by said correlating means;

known data portion output means for outputting in advance, a correlated output of the known data portion;

modulating/demodulating means for not performing multiplexing at the known data portion output from said known data portion output means and a subsequent specific data portion, and for multiplexing by delaying and combining data at a subsequent specific portion; and

input means for inputting an amount of information of data to be transmitted,

said modulating/demodulating means determining a number of multiplexing and an amount of delay based on the amount of information of data to be transmitted input from said input means.

5. A spread spectrum communication apparatus for transmission/reception using spread spectrum communication in such a data format that has a known data portion at a preamble portion, comprising:

correlating means for correlating a reception signal with a predetermined code;

detecting means for detecting the known data portion from the signal correlated by said correlating means;

known data portion output means for outputting in advance, a correlated output of the known data portion; and

modulating/demodulating means for not performing multiplexing at the known data portion output from said known data portion output means and a subsequent specific data portion, and for multiplexing by delaying and combining data at a subsequent specific portion,

said modulating/demodulating means determining a number of multiplexing and an amount of delay based on information from an upper layer.