JP4379658B2 - Receiver - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a receiving apparatus in digital wireless communication, and more particularly to a receiving apparatus capable of expanding the reception level of a baseband signal.
[0002]
[Prior art]
In digital wireless communication, since the reception input level varies greatly depending on the propagation distance, it is important to expand the input level width (that is, the reception dynamic range) that can be received. Conventionally, when demodulating a baseband signal, when performing level normalization processing for expanding the dynamic range, for example, when transmitting information in units of frames as in an FDMA (Frequency Division Multiple Access) system, one frame is transmitted. Secured in memory, normalization processing is performed for each secured frame.
[0003]
[Problems to be solved by the invention]
However, since the level normalization process in the conventional digital wireless communication is performed in units of frames by securing one frame in the memory, a large amount of memory is required. Also, for example, in the case of audio data that requires real-time processing, the level normalization processing in the conventional digital wireless communication is performed after securing one frame in the memory once, so that there is a processing delay in demodulation. There are problems such as sound delays. The present invention has been made in view of such circumstances, and an object of the present invention is to expand the reception dynamic range without impairing real-time performance and memory use efficiency by level normalization processing of the baseband signal. The object is to provide an excellent receiving apparatus.
[0004]
[Means for Solving the Problems]
In order to solve the above-described problems, a receiving apparatus of the present invention includes a radio unit that receives a radio signal, a received signal level control unit that performs level normalization processing of a baseband signal frequency-converted by the radio unit, and the reception unit The baseband signal is demodulated by the signal level control means and the baseband signal demodulation processing means for notifying the reception signal level control means of the level normalization processing timing. The received signal level control means includes an input level monitoring means for monitoring the level of the baseband signal, a normalized shift table holding means provided with a normalized shift number corresponding to the level of the baseband signal, and an input. Using the signal level determined by the level monitoring means, the table shifter creation means for obtaining the normalized shift number with reference to the normalized shift table holding means and the baseband signal input from the radio unit can be obtained by the table pointer creation means. And level control means for performing level normalization processing with the normalized shift number. Further, the input level monitoring means includes power calculating means for calculating signal power for part of the data of the baseband signal, level calculating means for calculating signal level for part of the data of the baseband signal, signal power and signal It is characterized by comprising level discriminating means for discriminating the level of the baseband signal based on the calculation result of at least one of the levels.
[0005]
That is, in the receiving apparatus of the present invention, the power or level is calculated for a part of the baseband signal data frequency-converted by the radio unit, and the level of the baseband signal is determined using this calculation result. Based on the above, the normalized shift number is obtained from the normalized shift table. Then, the level normalization processing of the baseband signal is performed with this normalized shift number. Therefore, with such a configuration, the level of the baseband signal can be determined from a part of the data of the baseband signal, and level normalization processing can be performed without impairing real-time performance and memory use efficiency.
[0006]
In the receiving apparatus of the present invention, the input level monitoring means includes a buffer for holding data, first correction data obtained by multiplying the data held in the buffer by a forgetting factor α, and a part of the data of the baseband signal. Buffer update means for updating the data content of the buffer to the calculation result obtained by adding the second correction data obtained by multiplying the signal power or signal level by the coefficient 1-α, and the baseband signal level based on the calculation result And a level discriminating means for discriminating.
[0007]
That is, with this configuration, it is possible to perform level determination in consideration of a sudden level fluctuation of the baseband signal due to fading.
[0008]
The receiving apparatus of the present invention further includes a line state determining unit that determines a line state from the signal demodulated by the baseband signal demodulation processing unit, and the normalized shift table holding unit is determined by the line state determining unit. And a table changing means for changing the normalized shift table referred to by the table pointer creating means based on the line state.
[0009]
That is, with such a configuration, it is possible to perform level normalization processing that is not easily affected by line conditions.
[0010]
The receiving apparatus of the present invention is also applied to a base station communication apparatus, a mobile station communication apparatus, and a radio communication system that obtains a normalized shift number from a part of data of a baseband signal and performs level normalization processing. be able to.
[0011]
Furthermore, the receiving apparatus of the present invention can be applied to a base station communication apparatus, a mobile station communication apparatus, and a wireless communication system that determine the level of a baseband signal using the forgetting factor α.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of a receiving apparatus according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram of a receiving apparatus according to the first embodiment of the present invention. FIG. 2 is a first block diagram for explaining the normalization processing timing operation of the input level monitoring means in FIG. FIG. 3 is a second block diagram for explaining the normalization processing timing operation of the input level monitoring means in FIG.
[0013]
First, the receiving apparatus according to the first embodiment will be described with reference to FIGS. 1, 2, and 3. In FIG. 1, a receiving apparatus includes a radio unit 1 that receives a radio signal, a received signal level control unit 2 that performs level normalization processing of a baseband signal that has been frequency-converted by the radio unit 1, and a received signal level control unit. And baseband signal demodulation processing means 3 for demodulating the baseband signal level-normalized by 2 and notifying the reception signal level control means 2 of the level normalization processing timing.
[0014]
The received signal level control means 2 also includes an input level monitoring means 11 for monitoring the level of the input baseband signal, and a normalized shift table having a normalized shift number corresponding to the level of the baseband signal as a normalized shift table. The holding means 12, the table boiler creation means 13 for obtaining the normalized shift number by referring to the normalized shift table holding means 12 using the signal level determined by the input level monitoring means 11, and the wireless unit 1 The level control unit 14 performs level normalization processing of the baseband signal with the normalization shift number obtained by the table pointer creation unit 13.
[0015]
Further, as shown in FIG. 2, the input level monitoring unit 11 calculates a signal level for a part of the baseband signal data, and a power calculation unit 15 for calculating the signal power for a part of the baseband signal data. The level calculation means 16 and the level determination means 7 for determining the level of the baseband signal based on the signal power calculation result or the signal level calculation result.
[0016]
Further, as shown in FIG. 3, the input level monitoring means 11 adds the forgetting coefficient to the data held in the buffer 19 in addition to the power calculation means 15, the level calculation means 16 and the level determination means 17 described in FIG. The calculation result obtained by adding the first correction data multiplied by α and the second correction data obtained by multiplying the signal power or signal level of a part of the baseband signal data by the coefficient 1−α is input, and the data of the buffer 19 is input. Can be constituted by a buffer update means 18 for updating the calculation result to a calculation result and a buffer 19 for storing update data based on the input information from the buffer update means 18.
[0017]
Next, the operation of the receiving apparatus in the first embodiment will be described. In FIG. 1, the baseband signal frequency-converted by the radio unit 1 is input to the received signal level control means 2. A part of the baseband signal input to the received signal level control means 2 is extracted by the input level monitoring means 11. Thereby, the input level monitoring means 11 receives the notification of the level normalization processing timing from the baseband signal demodulation processing means 3, and monitors the level of the baseband signal based on a part of the extracted baseband signal data.
[0018]
On the other hand, the normalized shift table holding unit 13 holds a table that associates the level of the baseband signal with the normalized shift number. Then, the table pointer creating means 12 obtains the normalized shift number by referring to the normalized shift table holding means 13 using the level of the baseband signal determined by the input level monitoring means 11. Further, the level control unit 14 performs a level normalization process on the baseband signal input to the reception signal level control unit 2 based on the normalized shift number obtained by the table boiler creation unit 12.
[0019]
As shown in FIG. 2, the input level monitoring means 11 extracts a part of the data of the baseband signal, calculates the power of the baseband signal by the power calculation means 15, and calculates the baseband signal power by the level calculation means 16. Calculate the level. Based on these calculation results, the level determining means 17 determines the level of the baseband signal.
[0020]
Further, when the input level monitoring means 11 as shown in FIG. 3 is used, power calculation is performed on the first correction data obtained by multiplying the data held in the buffer 19 by the forgetting factor α and a part of the data of the baseband signal. The signal power or signal level is obtained by means 15 or level calculation means 16 and added to the second correction data obtained by multiplying this by the coefficient 1-α. Further, the buffer update means 18 updates the data content of the buffer 19 to the added operation result. Then, the level discriminating unit 17 discriminates the level of the baseband signal from the calculation result.
[0021]
With such a configuration of the receiving apparatus, the level of the baseband signal can be determined from a part of the data of the baseband signal, and the level normalization process can be performed without impairing the real time property and the memory use efficiency.
[0022]
In addition, by using the level monitoring unit as shown in FIG. 3, it is possible to perform level determination in consideration of a sudden level fluctuation of the baseband signal due to fading.
[0023]
Next, a receiving apparatus according to the second embodiment of the present invention will be described. FIG. 4 is a block diagram of a receiving apparatus according to the second embodiment of the present invention. FIG. 5 is a block diagram for explaining the operation of the line state determination means and the table variable means in the second embodiment of the present invention.
[0024]
In the receiving apparatus of the second embodiment, in addition to the configuration of the receiving apparatus of the first embodiment shown in FIG. 1, line state determining means 4 for determining the line state is added as shown in FIG. Further, as shown in FIG. 5, the normalized shift table holding unit 12 includes a table variable unit 20 and a normalized shift table 21.
[0025]
Therefore, the contents described in the first embodiment are omitted, and the operation added in the second embodiment will be described. That is, in addition to the operation of the first embodiment, the line state determination unit 4 determines the line state based on the signal demodulated by the baseband signal demodulation processing unit 3 and normalizes the line state. This is notified to the table variable means 20 of the holding means 12.
[0026]
On the other hand, the table variable means 20 holds a normalized shift table 21 corresponding to the line state. Therefore, in the normalized shift table holding unit 12, the table variable unit 20 varies the normalized shift table 21 referred to by the table pointer creating unit 13 according to the line state based on the notified line state.
[0027]
Thus, with such a configuration, level normalization processing that is less susceptible to line conditions can be performed.
[0028]
The embodiment described above is an example for explaining the present invention, and the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the gist of the invention. For example, the above embodiment has been described with reference to a receiving device, but the present invention is not limited to this, and the same applies when applied to a base station communication device, a mobile station communication device, a wireless communication system, or the like using this receiving device. Needless to say, an effect can be obtained.
[0029]
【The invention's effect】
As described above, according to the present invention, the dynamic range of the demodulation processing means can be widened by performing level normalization processing on the input baseband signal in the receiving apparatus in digital wireless communication. In addition, since the normalized shift number is obtained using a part of the data of the baseband signal, the load processed by the receiving apparatus is not increased. Furthermore, since the level normalization process can be performed without losing the memory use efficiency while maintaining the real-time property, it can be preferably used for a receiving apparatus such as voice data that requires real-time processing. Of course, the same effect can be obtained when applied to a base station communication device, a mobile station communication device, or a wireless communication system using this receiving device.
[Brief description of the drawings]
FIG. 1 is a block diagram of a receiving apparatus according to a first embodiment of the present invention. FIG. 2 is a first block diagram for explaining the normalization processing timing operation of the input level monitoring means in FIG. FIG. 4 is a second block diagram for explaining the normalization processing timing operation of the input level monitoring means in FIG. 1. FIG. 4 is a block diagram of a receiving apparatus in the second embodiment of the present invention. FIG. 2 is a block diagram for explaining the operation of the line state discriminating means and the table variable means in the second embodiment.
DESCRIPTION OF SYMBOLS 1 Radio | wireless part 2 Received signal level control means 3 Baseband signal demodulation processing means 4 Line state discrimination means 11 Input level monitoring means 12 Normalized shift table holding means 13 Table boiler creation means 14 Level control means 15 Power calculation means 16 Level calculation Means 17 Level discriminating means 18 Buffer update procedure 19 Buffer 20 Table variable means 21 Normalized shift table

Claims (9)

A radio unit that receives a radio signal, a received signal level control unit that performs level normalization processing of a baseband signal that has been frequency-converted by the radio unit, and a baseband signal that has undergone level normalization processing by the received signal level control unit And a baseband signal demodulation processing means for notifying the reception signal level control means of the level normalization processing timing,
The received signal level control means includes:
Input level monitoring means for monitoring the level of the baze band signal;
A normalized shift table holding means comprising, as a normalized shift table, a normalized shift number corresponding to the level of the baseband signal;
A table boyer creating means for obtaining a normalized shift number by referring to the normalized shift table holding means using the signal level found by the input level monitoring means;
Level control means for performing level normalization processing on the baseband signal input from the radio unit with the normalized shift number obtained by the table pointer creating means,
The input level monitoring means is
Power calculating means for calculating signal power for a part of the data of the baseband signal;
Level calculation means for calculating the signal level for a part of the data of the baseband signal;
And a level discriminating unit that discriminates a level of a baseband signal based on a calculation result of at least one of the signal power and the signal level. The input level monitoring means includes:
A buffer to hold the data,
First correction data obtained by multiplying data held in the buffer by a forgetting factor α, and second correction obtained by multiplying a signal power or signal level calculated from a part of input baseband signal data by a factor 1-α. Buffer update means for updating the data content of the buffer to the calculation result obtained by adding the data;
The receiving apparatus according to claim 1, further comprising: a level determining unit that determines a level of a baseband signal based on the calculation result. Line state determining means for determining the line state from the signal demodulated by the baseband signal demodulation processing means;
The normalized shift table holding means is
3. The table variable unit according to claim 1, further comprising a table variable unit configured to vary a normalized shift table referred to by the table pointer generation unit based on the line state determined by the line state determination unit. Receiver device. The receiving apparatus according to claim 1, wherein the receiving apparatus is applied to a base station communication apparatus that obtains a normalized shift number from a part of data of a baseband signal and performs level normalization processing. The receiving apparatus according to claim 1, wherein the receiving apparatus is applied to a mobile station communication apparatus that obtains a normalized shift number from a part of data of a baseband signal and performs level normalization processing. The receiving apparatus according to claim 1, wherein the receiving apparatus is applied to a radio communication system that obtains a normalized shift number from a part of data of a baseband signal and performs level normalization processing. The receiving apparatus according to claim 2, wherein the receiving apparatus is applied to a base station communication apparatus that determines the level of a baseband signal using a forgetting factor α. The receiving apparatus according to claim 2, wherein the receiving apparatus is applied to a mobile station communication apparatus that determines a level of a baseband signal using a forgetting factor α. The receiving apparatus according to claim 2, wherein the receiving apparatus is applied to a radio communication system that determines a level of a baseband signal using a forgetting factor α.

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