KR100894454B1 - Detecting method of return signal in tdd type - Google Patents

Abstract

The present invention relates to a method for monitoring a carrier signal in a TDD scheme, the method comprising: a clock receiving step of receiving a system clock; A carrier signal branching step of branching a carrier signal transmitted from the transmitter antenna side to a transmitter signal output to the transmitter antenna side; A detecting step of detecting a branch signal branched in the carrier signal branching step with a voltage; A first average calculation step of calculating an average of a plurality of signal levels according to a plurality of voltages sequentially outputted through the detecting step in a transmission section of an arbitrary frame according to the system clock received in the clock receiving step; A second average calculating step of calculating an average of a plurality of averages calculated through the first average calculating step for a plurality of frames; And reporting the signal level according to the average calculated in the second average calculation step to a higher stage. By including the above, a technique for reducing the load on the system while allowing the signal level of the accurate carrier signal to be understood is disclosed.

TDD, carrier signal, signal monitoring, diagnosis, monitoring device

Description

Carrier signal monitoring method in TD method {DETECTING METHOD OF RETURN SIGNAL IN TDD TYPE}

1 is a block diagram of a signal monitoring apparatus capable of performing a carrier signal monitoring method in a TDD scheme according to an embodiment of the present invention.

2 is a flowchart illustrating a method for monitoring a carrier signal in a TDD scheme according to the present invention in the signal monitoring apparatus of FIG.

3 is a reference diagram graphically illustrating a frame of a signal in the TDD scheme.

The present invention relates to a method for monitoring a carrier signal in a TDD scheme.

In general, a mismatch (disconnection, short circuit, etc.) of a transmission antenna generates a carrier signal having a signal level above the matching standard. For example, when a transmission signal sent to the transmission antenna side generates a certain amount of carrier signals, the signal level of the carrier signal returned from the transmission antenna side is higher than the matching standard (e.g., the signal level of the transmission signal is 50 dBm). If the matching standard is 20dB, the signal transmission level of the carrier signal is 30dBm or more), which means that the transmission antenna is not matched, that is, it is mismatched. In this case, when the transmission antenna is mismatched (when the return signal is higher than the matching standard), the signal level of the transmission signal output through the transmission antenna is inevitably small, which causes problems in the communication quality such as a small communication radius. .

Therefore, by monitoring the signal level of the carrier signal to configure the monitoring device for monitoring the matching state of the transmission antenna, it is possible to immediately respond when an abnormality occurs in the matching state of the transmission antenna.

On the other hand, in WiBro, a portable Internet technology, a time division duplex (TDD) method that can save frequency resources is considered because the frequency band used is wide. In this TDD method, since a transmission signal section and a reception signal section are divided in one signal frame, a technique for a new monitoring method that can be applied to the TDD method is applied rather than the monitoring technique of the carrier signal used in the existing FDD method. It is required.

The present invention has been made in view of the above-described needs, and an object of the present invention is to provide a new carrier signal monitoring method that can be applied to the TDD scheme.

The carrier signal monitoring method in the TDD method according to the present invention for achieving the above object, the clock receiving step of receiving a system clock; A carrier signal branching step of branching a carrier signal transmitted from the transmitter antenna side to a transmitter signal output to the transmitter antenna side; A detecting step of detecting a branch signal branched in the carrier signal branching step with a voltage; A first average calculation step of calculating an average of a plurality of signal levels according to a plurality of voltages sequentially outputted through the detecting step in a transmission section of an arbitrary frame according to the system clock received in the clock receiving step; A second average calculating step of calculating an average of a plurality of averages calculated through the first average calculating step for a plurality of frames; And reporting the signal level according to the average calculated in the second average calculation step to a higher stage. Characterized in that it comprises a.

In the first average calculation step, a plurality of voltages sequentially output through the detecting step are compared to a comparison table to determine signal levels according to voltages, and then an average of the determined signal levels is calculated. It is another feature.

Each of the frames in the plurality of frames is further characterized by being spaced apart by at least one frame section.

Each of the frames in the plurality of frames is further characterized by being spaced apart by four frame sections.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment according to the present invention as described above will be described in detail.

1 is a block diagram of a signal monitoring apparatus 100 in which a carrier signal monitoring method is performed in a TDD scheme according to an exemplary embodiment of the present invention.

The signal monitoring apparatus 100 outputs the signal transmitted from the transmission antenna TxA side after being output to the transmission antenna TxA side through the band pass filter 200 and then detects the signal level of the detected carrier signal. Report to the upper level. Signal monitoring apparatus 100 is configured to include a branch means 110, reporting means 120 and the like to perform this role.

The branching means 110 is provided for branching a carrier signal carried from the transmission antenna TxA, and may be constituted by a directional coupler or the like.

The reporting means 120 is provided to report the signal level of the branch signal branched from the branching means 110 to a higher level, and includes a detector 121, a storage element 122, a central processor 123, and the like. do.

The detector 121 detects and outputs a branch signal branched by the branching means 110 with a voltage.

The storage element 122 stores a comparison table for a signal level (dBm) for each voltage of the signal. Table 1 below is an example of a comparison table.

TABLE 1

Output value (dBm) Detector (Voltage) 43.0 4.00 Measure 42.9 3.99 Calculation 42.8 3.98 Calculation 42.7 3.97 Calculation 42.6 3.96 Calculation 42.5 3.95 Calculation 42.4 3.94 Calculation 42.3 3.93 Calculation 42.2 3.92 Calculation 42.1 3.91 Calculation 42.0 3.90 Measure 41.9 2.90 Calculation 41.8 2.80 Calculation : : : : : : 21.0 1.80 Measure 20.9 1.79 Calculation 20.8 1.78 Calculation 20.7 1.77 Calculation : : : : : : 20.0 1.70 Measure 19.9 1.69 Calculation : : : : : : 18.0 1.50 Measure

As can be seen from Table 1, each of the plurality of voltages corresponds to each signal level dBm. Correspondence between voltage and signal level (dBm) according to Table 1 is measured or calculated by an experiment, for example, when the voltage (V) output through the detector 121 is 1.80 The signal level of was measured at 21dBm, the signal level when the voltage (V) output through the detector 121 is 1.50 means that the signal level is measured to 18.0. And the signal level of 0.1dB unit is calculated by dividing 1dB into 10 equal parts.

The central processor 123 compares the voltage V output from the detector 121 to a comparison table stored in the storage element 122 to determine the signal level of the transmission signal, and to sequentially output a plurality of frames in one frame. After calculating the average of the signal level of the carrier signal per frame for a plurality of signal levels determined according to the voltage (V), the average of each average obtained for a plurality of frames is calculated to The average calculated for the frame is determined as the signal level for the carrier signal, and this value is reported to the upper end. Detailed description thereof will be described later.

For reference, in FIG. 1, the signal monitoring device 100 and the band pass filter 200 are divided into separate configurations. However, according to implementation, the signal monitoring device 100 and the band pass filter 200 may be configured as a module in which the signal monitoring device and the band pass filter are integrated. .

The carrier signal monitoring method performed by the signal monitoring apparatus 100 configured as described above will be described in more detail with reference to the flowchart of FIG. 2.

1. Clock Receive <S210>

The central processor 123 receives a system clock from a system clock generator (not shown). The system clock is a signal indicating the start of a frame. In general, in the TDD scheme, one frame is divided into a transmission section and a reception section, and there are gaps TTG and RTG between the transmission section and the reception section. In addition, the transmission section, the reception section, the TTG, and the RTG are standardized to have an accurate time length. Therefore, when the starting point of the frame is known, the transmission section and the reception section can be known accurately.

2. Transmitting signal branch <S220>

The branching means 110 branches the transport signal which is output from the transmission antenna TxA side after being output to the transmission antenna TxA side through the band pass filter 200.

3. Detecting <S230>

The detector 121 detects and outputs the branch signal branched by the branching means 110 with the voltage V.

4. First Average Calculation <S240>

The CPU 123 compares each of the plurality of voltages V sequentially output from the detector 121 in the transmission section of a frame based on the input system clock to a comparison table, and compares the corresponding voltages V. FIG. After determining the signal levels according to the fields, an average of the determined signal levels is calculated. In the present embodiment, 55 voltages V are detected in one frame, signal levels according to each voltage V are determined, and an average of the determined signal levels is calculated. For example, when the voltage V output from the detector 121 is 1.78, the CPU 123 compares the voltage V of 1.78 to the table of Table 1 and compares the voltage V to 1.78. Determine that the corresponding signal level is 20.8dBm, determine this as the signal level of the carrier signal according to the corresponding voltage (V), repeat this process 55 times per frame, and calculate the average of the 55 signal levels obtained Will be done. In addition, step S240 is continuously repeated, which will be described in more detail with reference to FIG. 3.

3 is a graph of frames on the time axis in the TDD scheme. As shown in FIG. 3, the calculation of the first average is performed in a fifth frame spaced apart from the first frame by four frame intervals, assuming that the arbitrary frame is the first frame, and the second to fourth frames. Step S240 is not performed for. Of course, after the fifth frame, step S240 may be performed on the ninth frame, the thirteenth frame, .... This is because if the carrier signal is detected for each frame and the average is calculated, excessive load may be generated in the CPU 123 to cause system paralysis. Therefore, it was considered as an optimal method through experiments to perform step S240 while skipping at least one frame within the limit of maintaining accuracy. In this embodiment, it is determined by the experiment that the system load is maintained while maintaining the accuracy. Step S240 is performed while skipping four frames that are lines that can be minimized.

5. Second Average Calculation <S250>

When the averages for the plurality of frames (each of the plurality of frames are spaced apart by four frames) are all calculated by step S240, the average of the respective averages calculated for the plurality of frames is calculated. In the present embodiment, step S250 is performed once every 20 frames. That is, when an arbitrary frame is referred to as a first frame, an average of averages obtained through the step S240 is obtained for the first, fifth, ninth, thirteenth, and seventeenth frames. Of course, step S250 will be performed on the 21st, 25th, 29th, 33rd, and 37th frames in the future.

6. Report <S260>

The central processor 123 reports the average calculated through the step S250 to the upper stage.

As described above, the detailed description of the present invention has been made by the embodiments with reference to the accompanying drawings. However, since the above-described embodiments have only been described with reference to preferred examples of the present invention, the present invention is limited to the above embodiments. It should not be understood that the scope of the present invention is to be understood by the claims and equivalent concepts described below.

As described in detail above, the present invention has the following effects.

First, a new carrier signal monitoring method that can be applied to the TDD scheme is provided.

Second, the system load can be reduced because the carrier signal is measured with a gap (at least one frame period) of a predetermined time interval.

Claims (4)

A clock receiving step of receiving a system clock; A carrier signal branching step of branching a carrier signal carried from the transmitter antenna side by a transmitter signal output to the transmitter antenna side; A detecting step of detecting a branch signal branched in the carrier signal branching step with a voltage; A first average calculation step of calculating an average of a plurality of signal levels according to a plurality of voltages sequentially outputted through the detecting step in a transmission section of an arbitrary frame according to the system clock received in the clock receiving step; A second average calculating step of calculating an average of a plurality of averages calculated through the first average calculating step for a plurality of frames; And A reporting step of reporting a signal level according to the average calculated in the second average calculation step to a higher stage; Including, In the first average calculation step, a plurality of voltages sequentially output through the detecting step are compared to a comparison table to determine signal levels according to voltages, and then the average of the determined signal levels is calculated. Carrier signal monitoring method according to the TDD method. delete The method of claim 1, The carrier signal monitoring method of the TDD method, characterized in that each of the frames in the plurality of frames are spaced apart by at least one frame interval. The method of claim 3, The carrier signal monitoring method of the TDD method, characterized in that each of the frames in the plurality of frames are spaced apart by four frame intervals.

Images