KR20050097330A - Power detector of transferred signal strength indicator for wideband code division multiple access optical repeater - Google Patents

Abstract

The present invention relates to a transmission signal strength indicator (TSSI) power detector in a wideband code division multiple access (WCDMA) optical repeater. The present invention uses a switch at the front end of a system to expand the dynamic range. The internal controller can change the channel in 5MHz units, enabling fast power control. A TSSI power detector for a wideband code division multiple access optical repeater (WCDMA) according to the present invention includes a switching unit for switching high frequency (RF) signals to first and second paths having different gains by control signals; A first path unit configured to detect the first power by converting and amplifying the high frequency signal received from the switching unit with a local oscillation signal and then converting and amplifying the signal into a direct current (DC) voltage; A second path unit configured to variably amplify the high frequency signal received from the switching unit, mix and filter the local oscillation signal, and then convert and amplify the DC signal into a DC voltage to detect a second power; A comparison control unit generating the control signal to the switching unit by comparing the signals received from the first and second path units; And a phase locked loop (PLL) unit configured to generate the local oscillation signal to the first and second path units.

Description

POWER DETECTOR OF TRANSFERRED SIGNAL STRENGTH INDICATOR FOR WIDEBAND CODE DIVISION MULTIPLE ACCESS OPTICAL REPEATER for Wideband Code Division Multiple Access Optical Repeater

The present invention relates to a transmission signal strength indicator (TSSI) power detection device in a wideband code division multiple access (WCDMA) optical repeater. The present invention relates to a transmission signal strength indicator (TSSI) power detection device capable of detecting an area and enabling fast power control.

Recently, due to the development of wireless mobile communication technology, the form and range of users using services have been gradually expanded, and the third generation mobile communication system, Wideband Code Division Multiple Access (WCDMA), has emerged. And multiple channels that can be used by multiple users in the same frequency channel, but with greater channel capacity, faster data rates, and higher mobility than conventional Code Division Multiple Access (CDMA). Because of this approach, noise and interference from other users on the same channel can cause the adverse effect of reducing the overall system capacity. Therefore, in order to maximize the system capacity, WCDMA requires precise and fast power control within the service range of the base station or repeater, and the RF power detector is very important for this purpose.

1 is a block diagram of a power transmission and reception device for a repeater within a repeater according to the prior art, and is configured such that a transmission and reception side can jointly detect the power of a received signal and the power of a transmitted signal using a switch.

In the conventional power detector, as shown in FIG. 1, an Rx filter unit 11 for filtering a radio frequency (RF) received signal Rx received through an antenna ANT using an Rx channel filter according to a detection condition. And a variable low power amplifier 12 which variably amplifies the power of the RF received signal passing through the Rx filter unit 11 according to the linearity of the linear detector, and the base station to transmit through the antenna. The linearity of the linear detector detects the power of the RF transmission signal passing through the Tx filter unit 13 and the Tx filter unit 13 for filtering the RF transmission signal Tx using a Tx filter or a Tx channel filter according to a detection condition. A variable attenuator 14 that variably attenuates according to a range according to the above, a switch unit 15 for selecting a power detection path for detecting power of a received signal or power of a transmission signal using a switch; The switch A linear detector 16 for converting an RF reception signal or an RF transmission signal input according to the power detection path selected by the unit 15 into a DC voltage, and amplifying the DC voltage converted by the linear detector 16 It consists of a non-inverting amplifier 17.

However, WCDMA requires a power detector having a wide dynamic range capable of detecting even a weak signal. However, the conventional TSSI power detection device has a problem of having a narrower dynamic range. In addition, the conventional TSSI power detection device has a problem in fast power control because it performs a frequency search for each channel by the signal of the base station.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide two different gains from a single pole double throw (SPDT) switch having good isolation characteristics at the front end of an entire system in order to maximize the dynamic area. The present invention provides a TSSI power detector for a WCDMA optical repeater, which has branched into an excitation path and enables power detection according to a state of RF power input by adding a negative feedback circuit for actively selecting these paths according to power.

In addition, another object of the present invention is a control unit which is widely applied to a received signal strength indicator (RSI) power detector in order to take advantage of the ability to change the number of channels according to the type of service to the bandwidth of 5MHz per channel of WCDMA To provide a TSSI power detection device for the WCDMA optical repeater to change the band for each channel by using the added frequency converter and the phase-locked loop (PLL).

TSSI power detection apparatus for wideband code division multiple access optical repeater (WCDMA) according to the present invention for achieving the above object,

A switching unit for switching a high frequency (RF) signal into first and second paths having different gains by a control signal;

A first path unit configured to detect the first power by converting and amplifying the high frequency signal received from the switching unit with a local oscillation signal and then converting and amplifying the signal into a direct current (DC) voltage;

A second path unit configured to variably amplify the high frequency signal received from the switching unit, mix and filter the local oscillation signal, and then convert and amplify the DC signal into a DC voltage to detect a second power;

A comparison control unit generating the control signal to the switching unit by comparing the signals received from the first and second path units; And

And a phase locked loop (PLL) portion for generating the local oscillation signal to the first and second path portions.

The TSSI power detector may further include a controller configured to control the PLL unit so that the local oscillation signal is generated in a predetermined frequency unit.

The first path unit may include: a first mixing unit mixing the high frequency (RF) signal received from the switching unit and a local oscillation signal received from the PLL unit; A first band pass filter unit which filters and outputs only a signal of a specific channel to measure a high frequency (RF) signal received from the first mixer; A first power detector converting a high frequency (RF) signal received from the first band pass filter into a direct current (DC) voltage; And a first non-inverting operational amplifier configured to amplify the DC voltage received from the first power detector.

The second path unit may include a variable amplifying unit configured to variably amplify the high frequency (RF) signal received from the switching unit according to a range according to the linearity of the second power detector; A second mixing unit mixing a variable high frequency signal received from the variable amplifier unit and a local oscillation signal received from the PLL unit; A second band pass filter unit filtering only a signal of a specific channel to measure a high frequency (RF) signal received from the second mixing unit; A second power detector converting a high frequency (RF) signal received from the second band pass filter into a direct current (DC) voltage; And a second non-inverting operational amplifier configured to amplify the DC voltage received from the second power detector.

In addition, the PLL unit is characterized in that for monitoring the channel in 5MHz units.

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

2 is a block diagram of a TSSI power detection device in a repeater according to the present invention, the switching unit 110, the first mixing unit 120, the first band pass filter (BPF) unit 130, The first power detector 140, the first non-inverted operational amplifier 150, the variable amplifier 160, the second mixer 170, the second band pass filter 180, and the second power detector 190 ), A second non-inverting operational amplifier unit 200, a phase locked loop (PLL) unit 210, and a controller unit 220.

The switching unit 110 switches the high frequency (RF) signal received by the control signal received from the comparison controller 230 to the first and second paths A and B having different gains. do.

The first mixing unit 120 is a high frequency (RF) signal output to the first path (A) through the switching unit 110 and a local oscillation signal (local frequency signal) generated from the PLL unit 210 Mix it up.

The first band pass filter unit 130 filters and outputs only a signal of a specific channel to measure a high frequency (RF) signal received from the first mixing unit 120.

The first power detector 140 converts a high frequency (RF) signal received from the first band pass filter 130 into a direct current (DC) voltage.

The first non-inverting operational amplifier 150 amplifies the DC voltage received from the first power detector 140. At this time, the first power signal is detected (C) by the amplified signal.

The variable amplification unit 160 variably amplifies a high frequency (RF) signal output through the switching unit 110 to the second path B in accordance with the linearity of the second power detector 190. Outputs a variable high frequency signal.

The second mixer 170 mixes the variable high frequency signal received from the variable amplifier 160 and the local oscillation signal (local frequency signal) received from the PLL unit 210.

The second band pass filter unit 180 filters and outputs only a signal of a specific channel to measure a high frequency (RF) signal received from the second mixer 170.

The second power detector 190 converts a high frequency (RF) signal received from the second band pass filter 180 into a DC voltage.

The second non-inverting operational amplifier 200 amplifies the DC voltage received from the second power detector 190. At this time, the second power signal is detected (D) by the amplified signal.

The comparison controller 230 compares the direct current (DC) voltages received from the first and second non-inverting operational amplifiers 150 and 200 to the switching unit 110 through negative feedback. Output as a control signal.

The PLL unit 210 generates the local oscillation signal (local frequency signal) and outputs it to the first and second mixing units 120 and 170.

The controller unit 220 controls the PLL unit 210 to adjust the output signal of the PLL unit 210 in 5 MHz units.

The operation of the TSSI power detection apparatus according to the present invention configured as described above is as follows.

First, when the control signal fed back from the comparison control unit 230 is applied to the switching unit 110, the switching unit 110 has a first gain having a low gain of the high frequency (RF) signal received according to the control signal It is determined whether to switch to path A or to the second path B with high gain. However, since the level of power is not known in the initial state, the high frequency signal received in the second path B having a high gain is switched.

Subsequently, the high frequency (RF) power passing through the variable amplifier 160 and the peripheral attenuation circuit is variably amplified according to the linearity of the second power detector 190 to reduce noise.

The final high frequency (RF) signal passing through the variable amplification unit 160 and the peripheral attenuation circuit and the local oscillation signal generated by the PLL unit 210 (for example, a local frequency generated in 5 MHz units from a center frequency of 2070 MHz). Signal) is mixed in the second mixing unit 170 and converted into a desired band.

In this case, the TSSI power detection apparatus needs to detect power by dividing a channel in 5 MHz units in a total bandwidth of 20 MHz of wideband code division multiple access (WCDMA), so that the PLL unit 210 is controlled by the controller unit 220. Generates a local oscillation signal (local frequency signal).

The first and second band pass filter units 130 and 180 may be different from harmonic components generated during low-pass conversion by the first and second mixing units 120 and 170 and other components generated by the PLL unit 210. It will filter the frequencies of the band.

Thereafter, the filtered signals are converted into direct current (DC) voltages by the first and second power detectors 140 and 190.

The first and second non-inverting operational amplifiers 150 and 200 convert to a voltage level required by AGC (Automatic Gain Control), and send a signal to the negative feedback circuit.

Subsequently, the comparison control unit 230 generates a logic signal to enable the switch to operate based on the DC voltages from the first and second non-inverting operational amplifiers 150 and 200.

As described above, the switching unit 110 provided at the front end of the system branched into paths having different gains, and the RF power input by adding a negative feedback circuit for actively selecting these paths according to the power. Power detection is possible depending on the condition.

In addition, by using the PLL 210 and the controller 220, the bandwidth of 5 MHz per channel of WCDMA can be changed according to the type of service.

Preferred embodiments of the present invention as described above are disclosed for the purpose of illustration, and those skilled in the art will be able to make various modifications, changes, additions, etc. within the spirit and scope of the present invention, such modifications and changes belong to the following claims Should be seen.

As described above, according to the TSSI power detection apparatus for wideband code division multiple access (WCDMA) optical repeater according to the present invention, a wide dynamic region can be detected using a switch, and the wideband code division multiple access ( WCDMA) has the effect of enabling the fast power control required.

1 is a block diagram of a transmission and reception combined power detection device in a repeater according to the prior art

2 is a block diagram of an apparatus for detecting TSSI power in a repeater according to the present invention;

<Description of the symbols for the main parts of the drawings>

110: switching unit 120: first mixing unit

130: first band pass filter 140: first power detector

150: first non-inverting operational amplifier 160: variable amplifier

170: second mixing section 180: second band pass filter section

190: second power detection unit 200: second non-inverting operational amplifier unit

210: phase synchronization loop (PLL) unit 220: controller unit

Claims (5)

A transmission signal strength indicator (TSSI) power detector for a wideband code division multiple access (WCDMA) optical repeater, A switching unit for switching a high frequency (RF) signal into first and second paths having different gains by a control signal; A first path unit configured to detect the first power by converting and amplifying the high frequency signal received from the switching unit with a local oscillation signal and then converting and amplifying the signal into a direct current (DC) voltage; A second path unit configured to variably amplify the high frequency signal received from the switching unit, mix and filter the local oscillation signal, and then convert and amplify the DC signal into a DC voltage to detect a second power; A comparison control unit generating the control signal to the switching unit by comparing the signals received from the first and second path units; And A transmission signal strength indicator (TSSI) power detection device for a wideband code division multiple access (WCDMA) optical repeater, comprising a phase locked loop (PLL) portion for generating the local oscillation signal to the first and second path portions; . The apparatus of claim 1, wherein the transmission signal strength indicator (TSSI) power detection device comprises: And a controller unit for controlling the PLL unit so that the local oscillation signal is generated in a predetermined frequency unit. A transmission signal strength indicator (TSSI) power detection device for a wideband code division multiple access (WCDMA) optical repeater. The method of claim 1, wherein the first path portion, A first mixing unit mixing the high frequency (RF) signal received from the switching unit and a local oscillation signal received from the PLL unit; A first band pass filter unit which filters and outputs only a signal of a specific channel to measure a high frequency (RF) signal received from the first mixer; A first power detector converting a high frequency (RF) signal received from the first band pass filter into a direct current (DC) voltage; And A transmission signal strength indicator (TSSI) power detection for a wideband code division multiple access (WCDMA) optical repeater comprising a first non-inverting operational amplifier for amplifying a direct current (DC) voltage received from the first power detector Device. The method of claim 1 or 2, wherein the second path portion, A variable amplifier configured to variably amplify the high frequency (RF) signal received from the switching unit according to a range according to the linearity of the second power detector; A second mixing unit mixing a variable high frequency signal received from the variable amplifier unit and a local oscillation signal received from the PLL unit; A second band pass filter unit filtering only a signal of a specific channel to measure a high frequency (RF) signal received from the second mixing unit; A second power detector converting a high frequency (RF) signal received from the second band pass filter into a direct current (DC) voltage; And A transmission signal strength indicator (TSSI) power detection for a wideband code division multiple access (WCDMA) optical repeater comprising a second non-inverting operational amplifier for amplifying a direct current (DC) voltage received from the second power detector Device. The method according to claim 1 or 2, And said PLL unit monitors a channel in units of 5 MHz. 12. A transmission signal strength indicator (TSSI) power detection device for a wideband code division multiple access (WCDMA) optical repeater.