TWI491187B - Satellite receiver - Google Patents

Description

Satellite receiver

The present invention relates to a satellite receiver, and more particularly to a satellite receiver capable of automatically selecting a power input.

The user watches satellite TV by using satellite antennas to receive weak satellite signals and transmitting the satellite signals to satellite receivers (or low noise block down converters (LNBs). Then, satellite reception The device amplifies the received signal and lowers the RF signal to an Intermediate Frequency (IF), and then transmits the IF signal to the set top box.

The set-top box is often used in home entertainment systems, which include a tuner for obtaining a desired media program from the received intermediate frequency signal and outputting it to an audio receiver, television or other media playback device. In addition, the set-top box can be divided into an old-style set-top box that supports legacy and a new set-top box that supports channel stacking switch (CSS).

In general, the power of the satellite receiver is provided by the set-top box. When the satellite receiver is connected to different set-top boxes at the same time, the old set-top box may not provide enough power to the satellite receiver, enabling the satellite receiver to turn on the channel stacking switch function. Therefore, there is a need for a satellite receiver that automatically selects the power input.

The present invention provides a satellite receiver. The satellite receiver includes: a conventional switch; a channel stack switch; an RF module for receiving a satellite signal via an antenna; and a power module for providing a power to the first voltage according to a first voltage An RF module; and a selector for selectively providing the second voltage corresponding to the second voltage or the third voltage corresponding to the conventional one according to a second voltage on the channel stack switch A voltage is applied to the power module.

10‧‧‧Satellite Receiver System

20‧‧‧Old type set-top box

30‧‧‧New set-top box

40‧‧‧Antenna

100‧‧‧Satellite Receiver

110‧‧‧RF Module

120‧‧‧Power Module

130, 200‧‧‧ selector

C1, C2‧‧‧ capacitor

D1, D2‧‧‧ diode

GND‧‧‧ ground terminal

L1, L2‧‧‧ inductance

IN1, IN2‧‧‧ input

IF1, IF2‧‧‧ IF signal

M1-M3‧‧‧O crystal

OUT‧‧‧ output

P1‧‧‧ Traditional 埠

P2‧‧‧Channel Stacking Switch埠

PW‧‧‧ power supply

R1-R5‧‧‧ resistance

RF‧‧‧RF signal

V1-V3, Vs‧‧‧ voltage

1 is a view showing a satellite receiving system according to an embodiment of the present invention; and FIG. 2 is a view showing a selector according to an embodiment of the present invention.

The above and other objects, features and advantages of the present invention will become more <RTIgt; The satellite receiving system 10 of the embodiment. The satellite receiver system 10 includes a satellite receiver 100, an old set-top box 20, a new set-top box 30, and an antenna 40. The satellite receiver 100 is coupled to the old set-top box 20 through the conventional 埠P1 and coupled to the new set-top box 30 through the channel stack switch 埠P2. The satellite receiver 100 includes a radio frequency module 110, a power module 120, a selector 130, inductors L1 and L2, and capacitors C1 and C2. The capacitor C1 is coupled between the conventional 埠P1 and the RF module 110, and the capacitor C2 is coupled between the channel stack switch 埠P2 and the RF module 110. In addition, the inductor L1 is coupled to The conventional 埠P1 and the input terminal IN1 of the selector 130 are coupled between the channel stacking switch 埠P2 and the input terminal IN2 of the selector 130. When the satellite receiver 100 is connected to the old set-top box 20, the old set-top box 20 supplies the voltage V1 to the input terminal IN1 of the selector 130 via the conventional 埠P1 and the inductor L1. When the satellite receiver 100 is connected to the new set-top box 30, the new set-top box 30 provides a voltage V2 to the input terminal IN2 of the selector 130 via the channel stack switch 埠P2 and the inductor L2. In this embodiment, voltage V1 is substantially the DC voltage on conventional 埠P1, and voltage V2 is substantially the DC voltage on channel stack switch 埠P2. Then, according to the voltage level of the voltage V2, the selector 130 selectively supplies the voltage V1 or the voltage V2 to the output terminal OUT as the first voltage V3 of the power module 120. Then, the power module 120 can provide the power source PW to the radio frequency module 110 according to the first voltage V3. In this embodiment, the power module 120 is a DC to DC converter. Then, the radio frequency module 110 receives the radio frequency signal RF via the antenna 40 and generates the intermediate frequency signals IF1 and IF2 according to the radio frequency signal RF. Then, the RF module 110 transmits the intermediate frequency signal IF1 to the old set-top box 20 via the capacitor C1 and the conventional 埠P1, and the RF module 110 transmits the intermediate frequency signal IF2 to the channel stack switch 埠P2 via the capacitor C2 to New set-top box 30.

Figure 2 shows a selector 200 in accordance with an embodiment of the present invention. The selector 200 includes diodes D1 and D2, transistors M1-M3, and resistors R1-R5. The cathode and the anode of the diode D1 are respectively coupled to the output terminal OUT and the transistor M1, and the cathode and the anode of the diode D2 are respectively coupled between the output terminal OUT and the input terminal IN2, wherein the diode D1 The signal used by D2 to block the output OUT, respectively, will flow back to the input terminals IN1 and IN2. The transistor M1 is coupled between the diode D1 and the input terminal IN1. The resistor R1 is coupled to the transistor M1 Between the gate and the input terminal IN1. The transistor M2 is coupled between the gate of the transistor M1 and the ground GND. The resistor R2 is coupled between the input terminal IN1 and the transistor M3, and the resistor R3 is coupled between the gate of the transistor M2 and the resistor R2. The transistor M3 is coupled between the resistor R2 and the ground GND. The resistor R4 is coupled between the input terminal IN2 and the gate of the transistor M3, and the resistor R5 is coupled between the gate of the transistor M3 and the ground GND. In this embodiment, the transistor M1 is a P-type complementary metal oxide semiconductor (CMOS) transistor, and the transistors M2 and M3 are an N-type Bipolar Junction Transistor (BJT).

In FIG. 2, when the selector 200 receives only the voltage V2 from the input terminal IN2, the transistor M1 is non-conductive, and the selector 200 supplies the voltage V3 corresponding to the voltage V2 to the first via the output terminal OUT. The power module 120 of the figure, wherein the voltage level of the voltage V3 is determined by the voltage V2 and the turn-on voltage of the diode D2. In addition, when the selector 200 receives only the voltage V1 from the input terminal IN1, the transistor M1 is turned on, and then the selector 200 supplies the voltage V3 corresponding to the voltage V1 to the power module of FIG. 1 via the output terminal OUT. 120, wherein the voltage level of the voltage V3 is determined by the voltage V1 and the turn-on voltage of the diode D1. Furthermore, when the selector 200 simultaneously receives the voltage V1 from the input terminal IN1 and the voltage V2 from the input terminal IN2, the selector 200 controls whether the transistor M1 is turned on according to the voltage level of the voltage V2. First, the voltage V2 generates a voltage Vs through a voltage dividing circuit formed by the resistor R4 and the resistor R5. If the voltage V2 is too small for the voltage Vs to conduct the crystal M3, the voltage V1 from the input terminal IN1 is conducted through the resistor R2 and the resistor R3 to conduct the crystal M2. Next, the gate of the transistor M1 is grounded, and the transistor M1 is turned on. Then the selector 200 will provide a voltage V3 corresponding to the voltage V1 to the power module 120 of FIG. 1 via the output terminal OUT, so that the power module 120 can provide the power PW to the RF module according to the signal from the old set-top box 20. 110. Conversely, if the voltage V2 is sufficiently high that the voltage Vs can conduct the crystal M3, the transistor M3 will be turned on. Then, the gate of the transistor M2 is grounded, so the transistor M2 is not turned on. Therefore, the transistor M3 is not turned on, and the selector 200 supplies the voltage V3 corresponding to the voltage V2 to the power module 120 of FIG. 1 via the output terminal OUT, so that the power module 120 can be based on the new type of machine. The signal from the box 30 provides a power source PW to the RF module 110. Specifically, when the voltage level of the voltage V2 is greater than a specific value, the selector 200 provides the voltage V3 to the power module 120 according to the voltage V2, and when the voltage level of the voltage V2 is less than or equal to the specific value, The selector 200 provides a voltage V3 to the power module 120 according to the voltage V1. It is worth noting that this specific value is determined by the ratio of the resistor R4 to the resistor R5 and the turn-on voltage of the transistor M3. Therefore, based on the voltage V2 from the new form factor box, the selector 200 can determine whether or not to conduct the crystal M1. When the voltage V2 is less than or equal to a specific value, the transistor M1 is turned on, so that the satellite receiver is powered by the old-style table box. Furthermore, when the voltage V2 exceeds this particular value, the transistor M1 does not conduct, so that the satellite receiver is powered by the new form factor box.

Although the present invention has been disclosed in the above preferred embodiments, it is not intended to limit the invention, and it is intended that the invention may be modified and modified without departing from the spirit and scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims.

200‧‧‧Selector

D1, D2‧‧‧ diode

GND‧‧‧ ground terminal

IN1, IN2‧‧‧ input

M1-M3‧‧‧O crystal

OUT‧‧‧ output

R1-R5‧‧‧ resistance

V1-V3, Vs‧‧‧ voltage

Claims (10)

A satellite receiver includes: a conventional port; a channel stack switch; an RF module for receiving a satellite signal via an antenna; and a power module for providing a power source according to a first voltage to The radio frequency module; and a selector for selectively providing the second voltage corresponding to the second voltage or the third voltage corresponding to the conventional one according to a second voltage on the channel stack switch The first voltage is to the power module. The satellite receiver according to claim 1, wherein the selector provides the first voltage corresponding to the third voltage when the second voltage on the channel stack switch 小于 is less than or equal to a specific value To the above power module. The satellite receiver according to claim 1, wherein when the second voltage on the channel stack switch 大于 is greater than a specific value, the selector provides the first voltage corresponding to the second voltage to the above Power module. The satellite receiver of claim 1, wherein the selector comprises: a first diode having an anode coupled to the conventional crucible and a cathode coupled to an output; a second a pole body having an anode coupled to the channel stacking switch and a cathode coupled to the output terminal; a first transistor coupled to the anode of the first diode and the conventional a first resistor coupled between the gate of the first transistor and the conventional germanium; a second transistor coupled between the gate of the first transistor and a ground a second resistor coupled to the conventional resistor; a third resistor coupled between the second resistor and the gate of the second transistor; a third transistor coupled to the second resistor And a fourth resistor coupled between the gate of the third transistor and the channel stack switch ;; and a fifth resistor coupled to the gate of the third transistor and Between the above ground terminals. The satellite receiver according to claim 4, wherein the first voltage is a voltage of the output end of the selector, wherein when the second voltage on the channel stack switch 小于 is less than or equal to a specific value, The first transistor is conductive, and when the second voltage on the channel stack switch 大于 is greater than the specific value, the first transistor is non-conductive. The satellite receiver of claim 5, wherein the specific value is determined by the fourth resistor and the fifth resistor. The satellite receiver according to claim 4, wherein the first transistor is a P-type complementary MOS transistor, and the second transistor and the third transistor are N-type bipolar junctions. Crystal. For example, the satellite receiver described in claim 4 of the patent scope further includes: a first inductor coupled between the conventional transistor and the first transistor of the selector; a second inductor coupled between the channel stack switch 埠 and the anode of the second diode; The first capacitor is coupled between the RF module and the conventional cymbal; and a second capacitor is coupled to the RF module and the channel stack switch 埠. The satellite receiver according to claim 8, wherein when the conventional cymbal is coupled to a first set-top box, the radio frequency module provides a first intermediate frequency signal corresponding to one of the satellite signals to the first The upper radio frequency module provides a second intermediate frequency signal corresponding to one of the satellite signals to the second set top box when the channel stacking switch is coupled to a second set top box. The satellite receiver of claim 9, wherein the second voltage is provided by the first set-top box, and the third voltage is provided by the second set-top box.