JP2002374185A - Device and method for reception - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the power consumption of a receiving device that a portable telephone of CDMA system is equipped with. SOLUTION: When respective paths included in multi-path reception are allocated to respective fingers 1 to N that a demodulation part 20 has, it is decided each time whether the integral value of the reception levels of the respective paths exceeds an integral threshold X (step S13); when the integrated value of the reception levels exceeds the integrated threshold X (step S13: Yes), interruption processing is stopped (step S15), on the condition that there be a finger which can be allocated; but when the integral value of the reception levels does not exceed the integrated threshold X (step S13; No), the interruption processing is carried on until the number of fingers which have been allocated reaches the number N of fingers which can be allocated (step S14).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiving device provided in a portable telephone and a receiving method thereof.

[0002]

2. Description of the Related Art Recently, CDMA (Code Division Mu) has been used as an access method of a mobile phone capable of multi-channel.
A system using a spread spectrum technique called ltiple access (code division multiple access) has been proposed. This C
The DMA system separates channels by assigning different spreading codes to each user, and can set a larger number of user channels per frequency bandwidth than the conventional TDMA system.

[0003] In a receiving device provided in this CDMA mobile phone, a multipath received with a time difference (path delay time) or a phase difference due to the reflection of radio waves or the like is converted into a time and a time.
Due to the path diversity effect of rake reception in which phases are aligned and combined, it is possible to improve the reception characteristics of a mobile phone, thereby realizing high communication quality.

Here, in the rake reception, each symbol of the multipath included in the same channel whose reception timing is specified by a path searcher (path searcher 10 shown in FIG. 1) is converted to a finger (finger; FIG. 1
This is a reception process in which despreading is performed by a plurality of independent correlators called fingers 1 to N shown in FIG. 1), and the despread symbols are adjusted at the same timing and combined.

[0005] In order to follow the timing variation of the received multipath, the CDMA mobile phone periodically detects the multipath by the path searcher, and based on the detection result, determines the path of the path to the plurality of fingers. Update the assignment as needed.

Conventionally, when a plurality of multipaths are detected in the periodic multipath detection processing,
As long as the number of fingers that can be allocated permits, multipaths are allocated in order of path having the highest reception level. Here, the number of assignable fingers is set in advance for each reception channel.

Next, an example of multipath allocation to each finger will be described. FIG. 5 is a diagram illustrating an example of multipath allocation to each of the fingers 1 to 4 when the number of paths detected by the path searcher is equal to or less than the number of fingers that can be allocated, and FIG. FIG. 9 is a diagram illustrating an example of multipath allocation to fingers 1 to 4 when the number of paths is larger than the number of fingers that can be allocated;

The horizontal axis shown in FIGS. 5 and 6 represents a path delay time representing a difference between reception times for multipaths, and the vertical axis represents a reception level in each path.

In the example shown in FIG. 5, when the number of assignable fingers is 4 (fingers 1 to 4) and the number of paths detected by the path searcher is 3 (see reference numerals Q1 to Q3 in the figure), The path indicated by reference numeral Q1 in FIG.
The path indicated by reference numeral Q2 in FIG.
Are assigned to the fingers 2 respectively.

In the example shown in FIG. 6, when the number of assignable fingers is 4 (fingers 1 to 4) and the number of paths detected by the path searcher is 6 (see symbols R1 to R6 in the figure), The path indicated by reference numeral R1 in FIG.
The path indicated by reference numeral R2 in FIG.
Are assigned to the finger 3 and the path indicated by reference symbol R4 is assigned to the finger 4, respectively.
6 indicates that the path indicated by No. 6 is not assigned to any of the fingers 1 to 4.

[0011]

However, the above-mentioned conventional portable telephone has the following problems. In the receiving device provided in the above-mentioned conventional mobile phone, the paths detected by the path searcher are allocated to the assignable fingers as long as the number of fingers permits.

[0012] For this reason, among the paths detected by the path searcher, even if only a part of the paths has sufficient reception characteristics, the remaining paths that need not be further allocated are allocated. Electric power for operating these fingers that do not need to be allocated is wasted, and thus there has been a demand for more efficient power consumption.

For example, when there are three or more fingers that can be assigned, when three paths having a high reception level are detected by the path searcher under geographical conditions with good reception conditions, all three paths are detected by the path searcher. Each was assigned to a finger.

Further, for example, when two high-reception-level paths that can secure sufficient reception characteristics are detected, and then another high-reception-level bus is detected, the two high-reception-level buses are detected. In addition to the path, the path of the one more high reception level detected above is also assigned to the finger.

An object of the present invention is to reduce power consumption in a receiving device provided in a CDMA mobile phone and a receiving method thereof.

[0016]

According to the first aspect of the present invention,
Timing specifying means for specifying a reception timing for each transmission path in a multiplex wave transmission path for transmitting one communication data, and reception level detection for detecting a reception level for each communication data in the transmission path for which the reception timing is specified Means, and a demodulation means provided for each of the transmission paths, and a demodulation means for demodulating the communication data in the transmission path, wherein the reception level of the plurality of communication data detected by the reception level detection means is reduced. Accordingly, control means for controlling the assignment of the demodulation means for demodulating each communication data is provided.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A receiver 100 to which the present invention is applied will be described below in detail with reference to FIGS. The receiver 100 to which the present invention is applied is assumed to be a receiver mounted on a BB (Base Band) unit of a mobile phone (not shown) based on the CDMA system.

First, before describing the configuration of the receiver 100, an outline of the configuration of a mobile phone equipped with the receiver 100 and based on the CDMA system will be described. The mobile phone equipped with the receiver 100 includes, for example, a CPU (Central Processing Unit) and an R
An F (Radio Frequency) unit, a storage unit, an antenna, an input unit, an LCD (Liquid Crystal Display), a speaker, a microphone, and the like are provided (all are not shown except for the receiver 100).

The CPU provided in the mobile phone executes various processes in accordance with a predetermined program stored in the storage unit in accordance with an input instruction and input data from the input unit, and forms a processing result in the storage unit. Stored in a work memory area (not shown).
Or output to a speaker, or the BB unit, RF unit,
And transmit it to the outside via an antenna.

The BB unit includes a transmitter (not shown),
It includes a receiver 100 and the like to be described later, and performs frame processing and the like on communication data input from the RF unit and communication data output to the RF unit.

The key unit includes various operation keys such as an on-hook key, an off-hook key, a numeric keypad for mainly inputting a telephone number and character data, and an execution key (all are not shown). Various display information such as a menu screen, a mail editing screen, a search screen for searching a telephone directory, and an incoming call screen are displayed.

Next, the configuration of the receiver 100 to which the present invention is applied will be described. FIG. 1 is a block diagram showing the internal configuration of the receiver 100.

As shown in FIG. 1, a receiver 100 includes a path searcher 10, a demodulation unit 20, a finger manager 30,
It comprises a combining section 40 and the like.

Here, the path searcher 10 has the same functions as the functions of the timing specifying means and the reception level detecting means described in claim 1, and the demodulation section 20 and the finger manager 30 are respectively the demodulation means described in claim 1. It has the same functions as those of the means and control means.

The path searcher 10 detects the reception timing and the reception level of each path included in the received multipath, and transmits the detected data to the finger manager 3.
Output to 0.

The demodulation unit 20 includes a plurality of independent correlators called fingers, and despreads received data (symbols) with respect to the timing and the finger specified by the path searcher 10, and performs the despreading process. The obtained symbols of each path are output to the combining unit 40, respectively.
FIG. 1 shows assignable fingers 1 to N for a predetermined channel.

The finger manager 30 specifies the number N of fingers that can be assigned to each reception channel, and assigns paths to the fingers 1 to N of the demodulation unit 20 based on the detection data input by the path searcher 10. Control.

That is, the finger manager 30 selects the fingers 1 to N in order of the path having the highest reception level in the same channel among the paths whose reception timings have been detected.
Of the path to the server. At this time, the finger manager 30 accumulates the reception levels of the allocated paths each time, and compares the sum with the accumulation threshold value X stored in advance in the internal memory of the finger manager 30 (not shown).

Before the number of allocated fingers reaches the number of allocatable fingers, the finger manager 30
If the integrated value exceeds the integration threshold X, or if the number of allocated fingers reaches the number of assignable fingers before the integrated value exceeds the integration threshold X, the path allocation processing is stopped at that point. I do.

The synthesizing unit 40 performs a process of synchronizing (synchronizing) the symbols of each path input asynchronously from the demodulation unit 30, and then synthesizes each symbol.
Output to the subsequent stage.

Next, the operation of the receiver 100 to which the present invention is applied will be described. FIG. 2 is a flowchart illustrating a path assignment process in receiver 100.

First, the finger manager 30 previously stores the integrated threshold value X of the reception level for each path in the internal memory (step S10), and specifies the number N of fingers that can be allocated to each channel.

Next, when the finger manager 30 receives the multipaths in the predetermined channel, the path manager 10 detects the timing and the reception level of the multipaths by using the path searcher 10 and, at the same time, sorts the multipaths into the fingers 1 to N in order of the path having the higher reception level. (Step S11).

Referring now to FIGS. 3 and 4, an example of multipath allocation to each of the fingers 1 to N will be described.
FIG. 3 shows that the integrated value of the multipath reception level is the integrated threshold X.
FIG. 4 is a diagram showing an example of multipath allocation in a case where the number of allocated fingers reaches the number of allocatable fingers before the number of allocated fingers reaches the number of allocatable fingers. FIG. 9 is a diagram illustrating an example of multipath allocation when the integrated value of the reception level reaches an integrated threshold X;

The path searcher 10 shown in FIGS.
(The number of paths is six), which are the same, and each path is indicated by reference numerals A1 to A6 in the same drawing. Further, for the sake of simplicity, only one reception channel is shown in the present embodiment, and the number N of assignable fingers assigned to the multipath of this reception channel is four (finger). 1 to
4).

The horizontal axis shown in FIGS. 3 and 4 indicates a path delay time representing a difference between reception times of paths, and the vertical axis indicates a reception level in each path.

As shown in FIGS. 3 and 4, the finger manager 30 allocates the path indicated by reference numeral A1 in the drawing having the highest reception level among the received multipaths to the finger 1, and the next highest reception level in the drawing. The path indicated by reference sign A4 is assigned to the finger 2, and the reference sign A in FIG.
The path shown in 2 is assigned to the finger 3.

Returning to the flowchart of FIG. 2, the description will be continued. After the process of allocating paths to the fingers 1 to 4 shown in step S11, the finger manager 30 adds up the reception levels of the paths allocated to the fingers 1 to N each time (step S12).

For example, as shown in FIGS. 3 and 4, the paths indicated by reference numerals A1, A4, and A2 in FIG.
When assigning to -3, the reception levels of the assigned paths are integrated each time.

Next, the finger manager 30 determines whether or not the integrated value of the reception level in each path, which has been integrated in step S12, exceeds an integrated threshold value X stored in a built-in memory (not shown) of the finger manager 30. (Step S13).

In step S13, if the integrated value of the reception level of each path does not exceed the integrated threshold X (step S13; No), the finger manager 30
Determines whether the number of allocated fingers has reached the number N of fingers that can be allocated (step S14).

For example, as shown in FIGS. 3 and 4, when the number of fingers that can be allocated is 4, unless the integrated value of the reception level in each path reaches the integrated threshold X, the finger manager 30 determines the number of allocated fingers. Is determined each time whether or not has reached 4.

In step S14, if the number of allocated fingers has not reached the number N of fingers that can be allocated (step S14; No), the finger manager 30
Moves to step S11 to continue the finger assignment processing.

For example, as shown in FIG. 3, when the number of fingers that can be allocated is four, unless the integrated value of the reception level in each path reaches the integration threshold X, the fingers 1 to 4 are allocated until the number of allocated fingers reaches four. 4 is repeated.

In step S13, when the integrated value of the reception level of each path exceeds the integrated threshold X (step S13; Yes), the finger manager 30
The assignment process to each of the fingers 1 to N is stopped (step S15).

For example, as shown in FIG.
The assignment processing is performed on the fingers 1 to 3 in the order of the paths indicated by 1, 1, A4, and A2. When the integrated value of the reception level of each path exceeds the integration threshold X, the finger manager 30
Stops the allocation process to the fingers 1 to 4 without allocating the path indicated by the symbol A3 in the figure to the finger 4 even though one allocatable finger is available.

In step S15, each of the fingers 1 to
After stopping the allocation processing to N, the finger manager 30 outputs the symbol of each path despread in each of the fingers 1 to N to the synthesizing unit 40, and the synthesizing unit 40 outputs each of these asynchronously output symbols. After synchronizing the symbols of the paths, the symbols are synthesized (step S16).

As described above, when the receiver 100 to which the present invention is applied assigns each path included in the received multipath to each of the fingers 1 to N included in the demodulation unit 20, the reception level in each path is determined. Is the integration threshold X
Each time it is determined whether or not the sum exceeds the integration threshold value, the allocation process is stopped even if there are fingers that can be allocated, and the integrated value of the reception level Does not exceed the integration threshold X, a function is provided for continuing this allocation process until the number of allocated fingers reaches the number N of fingers that can be allocated.

Therefore, in a sufficiently stable reception state, even if only a part of the paths detected by the path searcher 10 has sufficient reception characteristics, a path that does not need to be allocated any more is selected. Since assignment to fingers can be avoided, power consumption for operating these fingers that do not need to be assigned can be reduced.
Power consumption can be reduced.

It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that the present invention can be appropriately modified without departing from the spirit of the present invention.

[0051]

According to the receiving apparatus of the present invention, reduction of power consumption can be realized in a receiving apparatus provided in a CDMA mobile phone.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an internal configuration of a receiver 100 to which the present invention has been applied.

FIG. 2 is a flowchart illustrating a path assignment process in a receiver 100 to which the present invention has been applied.

FIG. 3 is a diagram illustrating an example of multipath allocation in the receiver 100 to which the present invention is applied when the number of allocated fingers reaches the number of assignable fingers before the integrated value of the multipath reception level reaches the integration threshold X; FIG.

FIG. 4 is an example of multipath allocation in the receiver 100 to which the present invention is applied when the integrated value of the reception levels of the allocated paths reaches the integration threshold X before the number of allocated fingers reaches the number of allocatable fingers. FIG.

FIG. 5 is a diagram illustrating an example of multipath allocation to fingers 1 to 4 when the number of paths detected by a path searcher is equal to or less than the number of fingers that can be allocated in a receiving device provided in a conventional mobile phone.

FIG. 6 is a diagram illustrating an example of multipath allocation to each of fingers 1 to 4 when the number of paths detected by a path searcher is larger than the number of fingers that can be allocated in a receiving apparatus provided in a conventional mobile phone.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 receiver 10 path searcher 20 demodulation unit 30 finger manager 40 synthesis unit

Claims (6)

[Claims] 1. A timing specifying means for specifying a reception timing for each transmission line in a multiplex wave transmission line for transmitting one communication data, and a reception level for each communication data in the transmission line for which the reception timing is specified. A reception level detection unit for detecting, and a demodulation unit that is provided for each of the transmission paths and that demodulates the communication data in the transmission path, comprising: a plurality of communications detected by the reception level detection unit; A receiving apparatus comprising: a control unit that controls assignment of the demodulation unit that demodulates each communication data according to a data reception level. 2. The communication apparatus according to claim 1, further comprising: an accumulator for accumulating a reception level of the communication data allocated to each of the demodulators; wherein the controller accumulates each communication data in accordance with the accumulated value accumulated by the accumulator. 2. The receiving apparatus according to claim 1, wherein allocation of said demodulating means for demodulating is controlled. 3. If the integrated value exceeds a predetermined value before allocating the communication data to all of the demodulation units, the control means stops the allocation control and stops the control before the integrated value exceeds the predetermined value. 3. The receiving apparatus according to claim 2, wherein when the communication data is allocated to all of the demodulating means, the allocation control is stopped. 4. A step of specifying a reception timing for each transmission path in a multiplex transmission path for transmitting one communication data, and a step of detecting a reception level for each communication data on the transmission path whose reception timing is specified. Demodulating the communication data by demodulation means provided for each of the transmission paths. Demodulating each communication data according to the reception levels of the detected plurality of communication data. A receiving method including a step of controlling allocation of each of the demodulating means. 5. The communication apparatus according to claim 1, further comprising the step of integrating the reception level of said communication data allocated to each of said demodulation means, and the step of controlling the allocation of said demodulation means, wherein each communication is performed in accordance with said integrated value. 5. The receiving method according to claim 4, wherein allocation of said demodulation means for demodulating data is controlled. 6. The step of controlling the allocation of the demodulation means, wherein, if the integrated value exceeds a predetermined value before allocating the communication data to all of the demodulation means, the allocation control is stopped, and 6. The receiving method according to claim 5, wherein when the communication data is allocated to all of the demodulation means before the communication data exceeds a predetermined value, the allocation control is stopped.