Transmitter and receiver for multi-rated delay multiplexing direct spread spectrum communication system, and multi-rated delay multiplexing direct spread spectrum communication system

• US 6,738,448 B1
• Filed: 03/29/2000
• Issued: 05/18/2004
• Est. Priority Date: 11/04/1997
• Status: Expired due to Term

• 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): Jung, Min
• Assistant Examiner(s): Lee, Andy
• Application Number:
  US09/509,486
• Time in Patent Office: 1,511 Days
• Field of Search: 370/335, 370/742, 370/320, 375/146, 375/147, 375/130, 375/377
• US Class Current: 376/335
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity
• CPC Class Codes: H04W 52/52 using AGC [Automatic Gain Control] circuits or amplifiers

Abstract

A multi-rated delay multiplexing direct spread spectrum communication system the multiplicity of which can be changed. The system performs control operation as quickly as possible by suppressing the output fluctuation within a narrow range so as to perform constant power transmission. A gain-variable amplifier is provided at the succeeding stage of a modulator and the gain of the amplifier is controlled by a control signal generated based on the detection signal of the output of a power amplifying section. A detecting and control section detects the RF output of a delay multiplexing spread signal by a diode, finds the average power by an integrator, and equalizes the output of the amplifier to a comparation voltage by a control signal which is generated on comparing the average power with the comparation voltage. However, when the output of the amplifier is equalized to the comparation voltage, the time constant of the integration performed by the section is kept small for a fixed period of time by using a control signal representing a simplex/multiplex part. Consequently, a multiplexing switching section can quickly control the power.

Claims

1. A transmitter for a multi-rated delay multiplexing direct spread spectrum communication system comprising:

delay multiplexing means for multiplexing a series of signals obtained by delaying by a desired number of chips wherein each of said signals being directly spread with a same spreading code; and

transmission processing means for generating transmission signals by modulating the transmission signals which have been multiplexed by said delay multiplexing means and by converting a band of them, in which multi-rated transmission signals are generated in a format having a simplex part and a multiplex part having a given multiplicity; and

a control means for controlling the transmission power so that it is constant, and

in that said control means performs a control operation depending upon the multiplicity of said format.

2. The transmitter for a multi-rated delay multiplexing direct spread spectrum communication system as defined in claim 1, wherein said control means changes its control operation to make the transmission power constant for each multiplicity in response to a signal representative of the multiplicity which is determined by said format when the multiplexing operation is switched in response to the multiplicity representing signal.

3. The transmitter for a multi-rated delay multiplexing direct spread spectrum communication system as defined in claim 1 or 2, further comprises:

detecting means for detecting the transmission power output in said transmission processing means; and

means for controlling an amplified output of said transmission processing means in response to a detection output of said detecting means as said control means; and

wherein

a time constant of an integration of said detecting means being reduced in response to a multiplexing switching signal which is defined by said format at a period of transition at which multiplexing is switched.

4. The transmitter for a multi-rated delay multiplexing direct spread spectrum communication system as defined in claim 1, further comprises:

detecting means for detecting the transmission power output in said transmission processing means; and

means for controlling an amplified output of said transmission processing means in response to a detection output of said detecting means as said control means; and

wherein

a time constant of an integration of said detecting means being reduced in response to a signal representing a simplex part and a multiplexing switching signal which are defined by said format at a period of transition at which multiplexing is switched.

5. The transmitter for a multi-rated delay multiplexing direct spread spectrum communication system as defined in any one of claim 1, 2 or 4 to, further comprises:

detecting means for detecting the transmission power output in said transmission processing means;

said control means for controlling the amplified output of said transmission processing means in response to a detection output of said detecting means; and

means for converting an amplitude of a control signal from said control means in response to a multiplexing signal which is defined by said format.

6. The transmitter for a multi-rated delay multiplexing direct spread spectrum communication system as defined in any one of claim 1, 2 or 4, wherein if a digital operation is performed in said delay multiplexing means, changing of a multiplier for data to be multiplexed in said digital operation depending upon a signal representative of the multiplicity which is determined by said format is performed as one of said control means, so that an average amplitude is constant in square root among multiplicity including simplex.

7. The transmitter for a multi-rated delay multiplexing direct spread spectrum communication system as defined in any one of claim 1, 2 or 4, wherein if a digital operation is performed in said delay multiplexing means, a numerical value table which is referenced by the multiplexing data of a result of said digital operation is used as one of said control means;

and

in that data is output which makes the transmission power constant by changing said numerical value table in response to a signal representative of the multiplicity which is determined by said format.

8. The transmitter for a multi-rated delay multiplexing direct spread spectrum communication system as defined in claim 7, wherein for each multiplicity, there are provided said numerical value tables having numerical values which make a converted transmission power constant even if the numerical values which are given to a Digital/Analog (D/A) convertor for D/A data conversion after referencing to said numerical value tables are discrete, and

in that one of said numerical value tables is selected depending upon a signal representative of the multiplicity which is determined by said format.

9. The transmitter for a multi-rated delay multiplexing direct spread spectrum communication system as defined in claim 8, wherein if a Barker code of 11 chips is multiplexed and a 8 bit D/A convertor is used, the numerical values which are provided in each of said numerical value tables are

−

38, 38 when simplexing

−

54, 0, 54 when duplexing

−

66, −

22, 22, 66 when triplexing

−

76, −

38, 0, 38, 76 when quadruplexing

−

85, −

51, −

17, 17, 51, 85 for quintuplexing.

10. A receiver for multi-rated delay multiplexing direct spread spectrum communication system comprising:

receiving and processing means for receiving signals which are transmitted at an equal transmission output irrespective of multiplicity by multi-rating signals which are a spreading-code-spreaded, in a format having a multiplex part in which a plurality of series of signals each being delayed by a desired number of chips and a simplex part, and

in which gain adjustment in said receiving and processing means on reception is conducted depending upon a correlation output value,

wherein a reference comparison value which is compared with said correlation output value for generating a control signal of the gain adjustment is preset to a comparison value depending upon a power ratio of said multiplicity by a multiplexing switching part based upon said format.

11. A receiver for multi-rated delay multiplexing direct spread spectrum communication system comprising:

receiving and processing means for receiving signals which are transmitted at an equal transmission output irrespective of multiplicity by multi-rating signals which are a spreading-code-spreaded, in a format having a multiplex part in which a plurality of series of signals each being delayed by a desired number of chips and a simplex part, and

in which the gain adjustment in said receiving and processing means on reception is conducted depending upon a correlation output value,

wherein said correlation output value which is compared with a reference comparison value being used for generating a control signal for the gain adjustment, a correlation output value is used wherein the correlation output value is obtained by converting a correlation signal received depending upon a power ratio of its multiplicity by a multiplexing switching part based upon said format.

12. A multi-rated delay multiplexing direct spread spectrum communication system comprising:

a transmitter for multi-rated delay multiplexing direct spread spectrum communication including delay multiplexing means for multiplexing a series of signals obtained by delaying by a desired number of chips wherein each of said signals being directly spread with a same spreading code;

transmission processing means for generating transmission signals by modulating the transmission signals which have been multiplexed by said delay multiplexing means and by converting a band of them, in which multi-rated transmission signals are generated in a format having a simplex part and a multiplex part having a given multiplicity; and

a control means for controlling the transmission power so that it is constant, and in that said control means performs a control operation depending upon the multiplicity of said format; and

a receiver for multi-rated delay multiplexing direct spread spectrum communication including receiving and processing means for receiving signals which are transmitted at an equal transmission output irrespective of multiplicity by multi-rating signals which are a spreading-code-spreaded, in a format having a multiplex part in which a plurality of series of signals each being delayed by a desired number of chips and a simplex part, and in which gain adjustment in said receiving and processing means on reception is conducted depending upon a correlation output value, wherein a reference comparison value which is compared with said correlation output value for generating a control signal of the gain adjustment is preset to a comparison value depending upon a power ratio of said multiplicity by a multiplexing switching part based upon said format.

13. A multi-rated delay multiplexing direct spread spectrum communication system comprising:

a transmitter for a multi-rated delay multiplexing direct spread spectrum communication including delay multiplexing means for multiplexing a series of signals obtained by delaying by a desired number of chips wherein each of said signals being directly spread with a same spreading code;

transmission processing means for generating transmission signals by modulating the transmission signals which have been multiplexed by said delay multiplexing means and by converting a band of them, in which multi-rated transmission signals are generated in a format having a simplex part and a multiplex part having a given multiplicity; and

a control means for controlling the transmission power so that it is constant, and in that said control means performs a control operation depending upon the multiplicity of said format; and

a receiver for multi-rated delay multiplexing direct spread spectrum communication including receiving and processing means for receiving signals which are transmitted at an equal transmission output irrespective of multiplicity by multi-rating signals which are a spreading-code-spreaded, in a format having a multiplex part in which a plurality of series of signals each being delayed by a desired number of chips and a simplex part, and in which the gain adjustment in said receiving and processing means on reception is conducted depending upon a correlation output value, wherein said correlation output value which is compared with a reference comparison value being used for generating a control signal for the gain adjustment, a correlation output value is used wherein the correlation output value is obtained by converting a correlation signal received depending upon a power ratio of its multiplicity by a multiplexing switching part based upon said format.