TWI403117B - Broadcast receiver and method for regulating the same - Google Patents

Description

Broadcast receiver and adjustment method thereof

This invention relates to a broadcast receiver, and more particularly to a broadcast receiver that is dynamically adaptable to different input signal qualities.

For a broadcast receiver generally having a tuner, a value of a take-over point (TOP) is usually preset in the tuner, which is set in RF automatic gain control (RF AGC). The state replaces the IF automatic gain control (IF AGC) state, and the TOP value is related to the gain change or performance of the tuner. For example, if the TOP value is too large, the output signal of the tuner will be affected by the IF amplitude gain becoming smaller; conversely, if the TOP value is too small, the output signal of the tuner will be affected by the IF amplitude. The gain becomes larger and saturated.

On the other hand, the TOP value can be preset to replace the RF automatic gain control state in the intermediate frequency automatic gain control state; at this time, the output signal of the tuner may be affected by the TOP value becoming larger or smaller, thereby affecting the subsequent Signal processing. For this reason, it is very important to properly set the TOP value based on the input signal of the tuner.

It is an object of the present invention to provide a broadcast receiver whereby the quality of the transmitted signal therein is improved.

It is an object of the present invention to provide a method of adjusting a broadcast receiver whereby the performance of the broadcast receiver is improved.

One aspect of the present invention relates to a broadcast receiver including a tuning circuit and a demodulation circuit. The tuning circuit is used to tune an RF signal and output an intermediate frequency signal. The demodulation circuit is configured to demodulate the intermediate frequency signal transmitted by the variable tuning circuit, and output a command signal according to the quality of the intermediate frequency signal to change the value of the connection point in the tuning circuit.

Another aspect of the present invention relates to a broadcast receiver including a tuning circuit, a demodulation circuit, and a host circuit. The tuning circuit is used to tune an RF signal and output an intermediate frequency signal. The demodulation circuit is used to demodulate the intermediate frequency signal transmitted by the variable tuning circuit, and outputs a notification signal according to the quality of the intermediate frequency signal. The host circuit is configured to output a command signal according to the notification signal to change the value of the take-over point in the tuning circuit.

Yet another aspect of the present invention relates to a method for adjusting a broadcast receiver, wherein the broadcast receiver includes a tuning circuit and a demodulation circuit for tuning an RF signal to generate an intermediate frequency signal, and demodulating The variable circuit is used to demodulate the variable intermediate frequency signal. The method comprises: checking the quality of the intermediate frequency signal, and generating a command signal according to the quality of the intermediate frequency signal; and changing the value of one of the receiving points in the tuning circuit according to the command signal.

According to the technical content of the present invention, the method of applying the foregoing broadcast receiver and adjusting the broadcast receiver can not only improve the quality of the transmitted signal therein, but also improve the performance of the broadcast receiver and its ability to dynamically process signals.

FIG. 1 is a block diagram showing a broadcast receiver according to an embodiment of the invention. The broadcast receiver 100 includes a tuning circuit 110 and a demodulation circuit 120. The tuning circuit 110 further includes a radio frequency amplifier (not shown), and the radio frequency amplifier is coupled to an intermediate frequency amplifier (not shown). . In the tuning circuit 110, a value of a take-over point (TOP) is preset, which is set to an automatic gain control (AGC) state stop and another automatic gain control state to replace the takeover. For example, the TOP value is set in the RF Automatic Gain Control (RF AGC) state instead of the Intermediate Frequency Automatic Gain Control (IF AGC) state. The tuning circuit 110 is configured to tune a radio frequency signal and output an intermediate frequency signal correspondingly according to the TOP value. The demodulation circuit 120 is configured to demodulate the intermediate frequency signal transmitted by the variable tuning circuit 110, and output a command signal according to the quality of the intermediate frequency signal to change the preset TOP value.

Specifically, if the tuning circuit 110 outputs the intermediate frequency signal according to the preset TOP value, and the quality of the intermediate frequency signal, for example: bit error rate (BER), packet error rate (PER) , modulation error rate (MER) or signal-to-noise ratio (SNR), if not as good as expected or unable to meet a specific requirement, the demodulation circuit 120 will The command signal is output and the preset TOP value is changed. In addition, the demodulation circuit 120 may further include a monitoring circuit 122 for monitoring the quality of the intermediate frequency signal and correspondingly transmitting the command signal to the tuning circuit 110.

In an embodiment, two TOP values are pre-set in the tuning circuit 110, and when the tuning circuit 110 receives the command signal from the demodulation circuit 120, one of the TOP values changes to switch to another TOP value. That is, the TOP value is alternately changed between two predetermined TOP values. In another embodiment, the tuning circuit 110 is pre-set with a plurality of TOP values, and when the tuning circuit 110 receives the command signal from the demodulation circuit 120, the preset TOP value is cyclically (round -robin fashion) to make a change switch, where "loop" refers to a configuration that selects all the cells in a group in a fairly reasonable order, usually in a list from top to bottom, and then selects After that, restart the loop from the top of the list. In still another embodiment, the demodulation circuit 120 sets a preset TOP value in the tuning circuit 110 according to a radio frequency amplifier at different gain values, and the preset TOP value is received by the tuning circuit 110. The command signal transmitted from the circuit 120 is set.

2 is a block diagram showing a broadcast receiver according to another embodiment of the present invention. The broadcast receiver 200 includes a tuning circuit 210, a demodulation circuit 220, and a host circuit 230. The tuning circuit 210 further includes a radio frequency amplifier (not shown) in practical applications, and the radio frequency amplifier is subsequently coupled to the intermediate frequency amplifier. (not shown). The tuning circuit 210 is configured to tune the RF signal and output the intermediate frequency signal correspondingly according to the TOP value. The demodulation circuit 220 is configured to demodulate the intermediate frequency signal transmitted by the variable tuning circuit 210, and output a notification signal according to the quality of the intermediate frequency signal. In addition, the demodulation circuit 220 may further include a monitoring circuit 222 for monitoring the quality of the intermediate frequency signal and correspondingly generating the notification signal. The host circuit 230 is configured to receive the notification signal sent by the demodulation circuit 220, and output a command signal according to the notification signal to change the preset TOP value, wherein the host circuit 230 can be a chip, a processor, etc. element.

Similarly, if the tuning circuit 210 outputs the intermediate frequency signal according to the preset TOP value, and the quality of the intermediate frequency signal, for example, a bit error rate (BER), a packet error rate (PER), The modulation error rate (MER) or the signal-to-noise ratio (SNR) is not as good as expected or cannot meet a specific requirement, and the demodulation circuit 220 outputs The signal is signaled to notify the host circuit 230 that the host circuit 230 is notified to transmit the command signal to the tuning circuit 210. In addition, the preset TOP value may also be alternately changed between two predetermined TOP values, cyclically changed between multiple TOP values, or set according to different gain values to another TOP. value.

The above TOP value can be set in different ways. One of the following is an embodiment for setting the TOP value in the tuning circuit. FIG. 3 is a schematic diagram showing the relationship between the RF gain and the intermediate frequency gain and the relationship between the RF gain and the IF signal quality when the level of the RF signal is not changed according to an embodiment of the present invention. In the third diagram, in more detail, as the RF gain increases, the IF gain decreases. In the A area and the B area as shown in Fig. 3, the RF gain is too small, so that the quality of the intermediate frequency signal is affected and cannot meet certain requirements. In the C region as shown in Fig. 3, the quality of the intermediate frequency signal is maintained in a good state. In the D area and the E area as shown in FIG. 3, the intermediate frequency signal is saturated due to the increase in the radio frequency gain, and the quality of the intermediate frequency signal is again deteriorated. As can be seen from the above, the TOP value can be set in the C area as shown in Fig. 3.

However, since the quality of the IF signal may vary in the C region, and the best quality of the IF signal may fall in the B or D region near the C region, the following provides another way to set the tuning circuit. The implementation of the TOP value.

In another embodiment, the TOP value can be set by accumulating the gain value weighted by the intermediate frequency amplifier, wherein the gain value of the intermediate frequency amplifier corresponds to the gain value of the radio frequency amplifier, respectively, and the gain value of the intermediate frequency amplifier is based on The quality of the IF signal is weighted. Specifically, the plurality of gain values of the radio frequency amplifier are set within a predetermined range, and the gain value of the intermediate frequency amplifier corresponding to the gain value of the radio frequency amplifier is thereby obtainable. In addition, when the quality of the intermediate frequency signal exceeds a predetermined threshold, the gain value of the intermediate frequency amplifier is accumulated with weights, and the TOP value in the tuner is set according to the cumulative result. The following will be described by way of an example.

FIG. 4 is a flow chart showing the acquisition of a TOP value according to an embodiment of the invention. First, the RF automatic gain control (RF AGC) is turned off, the intermediate frequency automatic gain control (IF AGC) is activated, and the RF gain is set to a minimum value (step 402). Next, the program waits for a predetermined period of time (step 404) so that the corresponding intermediate frequency gain can be stably acquired according to the radio frequency gain. Thereafter, it is determined whether the intermediate frequency gain is stable (step 406). If the intermediate frequency gain is unstable, then the flow returns to step 404. Conversely, if the intermediate frequency gain is stable, it is determined whether the quality of the intermediate frequency signal exceeds a predetermined threshold THD (step 408). Furthermore, if the quality of the intermediate frequency signal exceeds a predetermined threshold THD, the weight corresponding to the intermediate frequency signal quality (eg, proportional to the quality of the intermediate frequency signal) is specified, and the corresponding intermediate frequency gain and its weight are recorded. (Step 410). In an embodiment, the above weights may be set as a function of the quality of the intermediate frequency signal. Figure 5 is a schematic diagram showing the relationship between weight and signal quality in accordance with an embodiment of the present invention. As shown in Fig. 5, when the quality of the intermediate frequency signal exceeds the predetermined threshold THD, if the quality of the intermediate frequency signal is better, the weight is larger. After step 410, the RF gain is increased (step 412). On the other hand, if the quality of the intermediate frequency signal does not exceed the predetermined threshold THD, the RF gain is directly increased (step 412).

Then, it is determined whether the increased RF gain exceeds the maximum value of the RF gain (step 414). If the increased RF gain does not exceed the maximum RF gain, then the flow returns to step 404 to acquire another corresponding intermediate frequency gain based on the RF gain. Conversely, if the increased RF gain exceeds the maximum RF gain, the TOP value can be obtained by accumulating the recorded intermediate frequency gain value and its additional weight (step 416). For example, the TOP value can be calculated by the following equation:

Where γ represents an index relative to the recorded intermediate frequency gain and its weight.

FIG. 6 is a flow chart showing an adjustment of a broadcast receiver according to an embodiment of the invention. First, check the quality of the intermediate frequency signal (step 602), for example: bit error rate (BER), packet error rate (PER), modulation error rate (MER) or A parameter such as a signal-to-noise ratio (SNR) or a combination of the above parameters. Next, the preset TOP value in the tuning circuit of the broadcast receiver is changed according to the result of the check (step 604). For example, the TOP value can be alternately changed between two predetermined TOP values in the tuning circuit, or changed in a cyclic manner between a plurality of TOP values. In step 604, as shown in FIG. 1, the command signal is generated by the demodulation circuit 120 according to the result of the check, and then the command signal is transmitted back to the tuning circuit 110 to change the TOP value; or as shown in FIG. It is shown that the notification signal is generated by the demodulation circuit 220 according to the result of the inspection, and then the command signal is generated by the demodulation circuit 220 and then the host circuit 230 according to the notification signal, so that the TOP value can be changed and switched according to the instruction signal.

In another embodiment, after checking the quality of the intermediate frequency signal (step 602), an appropriate TOP value is first acquired based on the RF amplifier at different RF gain values (step 606). For example, first, a plurality of gain values of the radio frequency amplifier are set within a predetermined range; then, a gain value of the intermediate frequency amplifier corresponding to the gain value of the radio frequency amplifier is obtained; and then, the quality of the intermediate frequency signal exceeds a predetermined threshold value. At the time, the gain value of the IF amplifier is accumulated with the weight to obtain an appropriate TOP value. Thereafter, the preset TOP value in the tuning circuit of the broadcast receiver is switched to the appropriate TOP value (step 604).

It can be seen from the above embodiments of the present invention that the application of the foregoing broadcast receiver and the method of adjusting the broadcast receiver can not only improve the quality of the transmitted signal, but also improve the performance of the broadcast receiver and its ability to dynamically process signals.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and the present invention can be modified and modified without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached.

100, 200. . . Broadcast receiver

110, 210. . . Tuning circuit

120, 220. . . Demodulation circuit

122, 222. . . Supervisory circuit

230. . . Host circuit

402～416, 602～606. . . step

FIG. 1 is a block diagram showing a broadcast receiver according to an embodiment of the invention.

2 is a block diagram showing a broadcast receiver according to another embodiment of the present invention.

FIG. 3 is a schematic diagram showing the relationship between the RF gain and the intermediate frequency gain and the relationship between the RF gain and the IF signal quality when the level of the RF signal is not changed according to an embodiment of the present invention.

FIG. 4 is a flow chart showing the acquisition of a TOP value according to an embodiment of the invention.

Figure 5 is a schematic diagram showing the relationship between weight and signal quality in accordance with an embodiment of the present invention.

FIG. 6 is a flow chart showing an adjustment of a broadcast receiver according to an embodiment of the invention.

100. . . Broadcast receiver

110. . . Tuning circuit

120. . . Demodulation circuit

122. . . Supervisory circuit

Claims (14)

A broadcast receiver comprising: a tuning circuit for tuning an RF signal to output an intermediate frequency signal; and a demodulation circuit for demodulating the intermediate frequency signal transmitted by the tuning circuit, and The quality of the intermediate frequency signal outputs a command signal to change a value of a takeover point in the tuning circuit; wherein the tuning circuit includes an RF amplifier, the RF amplifier is then coupled to an intermediate frequency amplifier, and the demodulation is converted The circuit system sets the value of the take-over point according to the RF amplifier at different gain values, and the gain value of the IF amplifier corresponds to the gain value of the RF amplifier respectively; wherein when the quality of the IF signal is greater than a predetermined threshold The gain value of the intermediate frequency amplifier is weighted according to the weight corresponding to the quality of the intermediate frequency signal, and the value of the takeover point is set by accumulating the weighted value of the intermediate frequency amplifier. The broadcast receiver of claim 1, wherein the value of the take-over point in the tuning circuit alternates between values of two predetermined take-over points. The broadcast receiver of claim 1, wherein the value of the take-over point in the tuning circuit is changed in a cyclic manner between values of the plurality of take-over points. The broadcast receiver according to claim 1, wherein the demodulation circuit is based on a bit error rate, a packet error rate, and a modulation error of the intermediate frequency signal. The command signal is output at a rate or a signal ratio. A broadcast receiver includes: a tuning circuit for tuning an RF signal to output an intermediate frequency signal; and a demodulation circuit for demodulating the intermediate frequency signal transmitted by the tuning circuit, and according to the The quality of the intermediate frequency signal outputs a notification signal; and a host circuit for outputting a command signal according to the notification signal to change a value of a connection point in the tuning circuit; wherein the tuning circuit comprises an RF amplifier, the RF The amplifier is then coupled to an intermediate frequency amplifier, and the demodulation circuit sets the value of the take-over point according to the RF amplifier at different gain values, and the gain value of the intermediate frequency amplifier corresponds to the gain value of the RF amplifier respectively. Wherein when the quality of the intermediate frequency signal is greater than a predetermined threshold, the gain value of the intermediate frequency amplifier is weighted according to the weight corresponding to the quality of the intermediate frequency signal, and the value of the takeover point is accumulated by weighting Set the gain value of the IF amplifier. The broadcast receiver of claim 5, wherein the value of the take-over point in the tuning circuit alternates between values of the two predetermined take-over points. The broadcast receiver of claim 5, wherein the value of the take-over point in the tuning circuit is changed in a cyclic manner between values of the plurality of take-over points. The broadcast receiver according to claim 5, wherein the demodulation circuit outputs the notification signal according to a bit error rate, a packet error rate, a modulation error rate, or a signal-to-noise ratio of the intermediate frequency signal. A method for adjusting a broadcast receiver, wherein the broadcast receiver includes a tuning circuit and a demodulation circuit for tuning an RF signal to generate an intermediate frequency signal, and the demodulation circuit is used Demodulating the IF signal, the method comprising: checking a quality of the IF signal, and generating a command signal according to the quality of the IF signal; and changing a value of a takeover point in the tuned circuit according to the command signal, The tuning circuit includes a radio frequency amplifier, and the radio frequency amplifier is coupled to an intermediate frequency amplifier, and the value of the connection point is set according to the radio frequency amplifier under different gain values, wherein the step of setting the value of the connection point further includes Setting a plurality of gain values of the radio frequency amplifier within a predetermined range; obtaining a plurality of gain values of the intermediate frequency amplifier corresponding to the gain values of the radio frequency amplifier, wherein a quality of the intermediate frequency signal is greater than a critical value The gain value of the intermediate frequency amplifier is weighted according to the weight corresponding to the quality of the intermediate frequency signal; when the quality of the intermediate frequency signal exceeds the When the predetermined threshold value, the cumulative gain by the plurality of the weighted sum of the intermediate frequency amplifier; and a set point value of the receiver according to the accumulation result. The method of claim 9, wherein the value of the take-over point in the tuning circuit alternates between values of the two predetermined take-over points. The method of claim 9, wherein the value of the take-over point in the tuning circuit is cyclically changed between values of the plurality of take-over points. The method of claim 9, wherein the step of checking the quality of the intermediate frequency signal further comprises: checking a bit error rate, a packet error rate, a modulation error rate or a signal to noise ratio of the intermediate frequency signal. The method of claim 9, wherein the command signal is generated by the demodulation circuit based on the quality of the intermediate frequency signal. The method of claim 9, wherein the command signal is generated by a host of the demodulation circuit followed by the quality of the intermediate frequency signal.