Examples
As shown in FIG. 1, the method for controlling a digital wireless repeater provided by the present invention comprises the following steps:
step 1, respectively carrying out low-noise amplification on a received downlink signal and an uplink signal, and dividing the downlink signal after low-noise amplification into a first downlink signal and a second downlink signal;
the step 1 also comprises the following steps:
step 1.1, testing the first downlink signal channel by channel to obtain information source information;
step 1.2, locking an information source;
step 1.3, obtaining configuration parameters of the locked information source, and setting the configuration parameters into a downlink and/or an uplink of the digital wireless repeater;
step 2, respectively carrying out down-conversion processing and analog-to-digital change on the second downlink signal and the uplink signal after low-noise amplification in corresponding links;
step 3, respectively detecting the signals obtained in the step 2 in a digital domain and processing the signals according to the detection result;
step 4, respectively carrying out digital-analog change and up-conversion processing on the signals obtained in the step 3 in corresponding links;
and 5, respectively transmitting the signals obtained in the step 4.
The control method of the intelligent digital wireless repeater can realize the functions of information source testing and information source selection, and the step 1 is described in detail below, specifically, a repeater receives a downlink signal, a part of the downlink signal is amplified and coupled through low noise amplifier to perform channel-by-channel testing, and information of all information sources (including broadcast channel frequency point numbers, cell identification codes, location area identification codes, signal-to-noise ratios, telephone traffic and the like) in the area where the repeater is located is obtained by analyzing the information of a broadcast channel and a control channel on each frequency point; and selecting a proper cell information source according to the acquired information, and locking the cell information source. And acquiring configuration parameters of the information source and setting the configuration parameters into a downlink and/or an uplink of the digital wireless repeater. Therefore, the functions of automatically selecting the information source and automatically setting the frequency point are realized.
In order to realize the information source frequency point tracking function, the method for controlling the digital wireless repeater further comprises the following steps of 1: step 1.4, judging whether the configuration parameters change, if so, re-acquiring the configuration parameters, setting the re-acquired configuration parameters into a downlink and/or an uplink of the digital wireless repeater, and updating and setting the frequency points in real time.
If the repeater is not properly designed and debugged, the repeater may be self-excited, mainly because the donor antenna and the cover antenna are both transceiving antennas, because the power of the receiving antenna and the power of the repeating antenna of the wireless co-frequency repeater are the same, if the isolation does not meet the requirement, the donor antenna may receive the output signal of the cover antenna, and then the output signal is amplified by the repeater and transmitted by the cover antenna, and the transmitted signal is received by the donor antenna, and the above steps are repeated to form a positive feedback signal, so that the noise signal is continuously amplified to generate self-excitation, therefore, the adverse effect caused by self-excitation should be eliminated when the digital repeater is designed.
The step 2 comprises the following steps:
step 2.1, filtering the second downlink signal and the uplink signal after low-noise amplification in a corresponding link;
step 2.2, respectively carrying out down-conversion processing on the signals obtained in the step 2.1 in corresponding links;
step 2.3, respectively filtering the signals obtained in the step 2.2, and then carrying out modulus change;
the step 4 comprises the following steps:
step 4.1, filtering the signals obtained in the step 3 after digital-to-analog change in corresponding links;
step 4.2, the signals obtained in the step 4.1 are subjected to up-conversion in corresponding links respectively;
step 4.3, the signals obtained in the step 4.2 are respectively filtered and amplified in corresponding links;
the filtering in the steps mainly filters out-of-band spurious signals and improves the selectivity of carrier waves;
step 3 also comprises the following steps:
adaptively canceling feedback signals in corresponding links in a digital domain respectively; feedback signals comprising signals transmitted by the coverage antenna received by the donor antenna and signals transmitted by the donor antenna received by the coverage antenna;
judging whether the difference value between the antenna isolation of the coverage antenna and the donor antenna and the gain of the repeater is larger than a preset value or not;
if not, adjusting the gain of the repeater to ensure that the difference between the antenna isolation and the gain of the repeater is greater than a preset value. The preferred preset value is 15dB.
In addition, the amplified noise floor in the uplink of the digital repeater can seriously affect the sensitivity of the repeater, and in addition, the duplexer is easy to burn out when being in a saturated state for a long time, so that the uplink noise is required to be effectively inhibited.
The invention discloses a control method of a digital wireless repeater, and the step 3 further comprises the following steps: detecting the time slot power of each uplink carrier in an uplink channel, and respectively judging whether the time slot power of each uplink carrier is lower than a power threshold value; if yes, the weak power time slot on the corresponding carrier is turned off. Therefore, the uplink noise power from the repeater to the base station is reduced, and the interference of the repeater to the base station is eliminated.
Meanwhile, accurate power control and gain self-adaptive adjustment are key technical requirements of the repeater system. Accurate power control and gain adaptation help ensure efficient and reliable operation of the system. Thus, step 3 further comprises: the input power strength of the signal in each link is detected respectively, and the output power and the gain of each link reach the preset requirements by controlling the gain in the corresponding link. In order to realize the adjustment of the gain of the repeater, a plurality of gain adjustable amplifiers can be arranged in the repeater, and the gain adaptive adjustment function of the repeater can be achieved by adjusting the gain adjustable amplifiers.
The control method of the intelligent digital wireless repeater further comprises a method for realizing the adjusting function of a donor antenna and a coverage antenna connected with the repeater, and specifically comprises the following step 1.1:
in the scanning process of all channels in the space, the power and the channel quality of each channel are obtained;
adjusting a horizontal inclination angle and a vertical inclination angle of a donor antenna externally connected with the intelligent digital wireless repeater; until the needed signal is strongest and the signal quality is best, judging that the donor antenna is aligned to the base station at the moment;
and adjusting the horizontal inclination angle and the vertical inclination angle of a coverage antenna externally connected with the intelligent digital wireless repeater until the isolation degree of the antenna is maximum. Through the steps, the self-adaptive adjustment of the donor antenna 101 and the self-adaptive adjustment of the coverage antenna 107 are realized, so that the repeater can obtain the optimal information source and the optimal isolation.
As shown in fig. 2, the intelligent digital wireless repeater of the present invention includes a DT port duplexer 102, an MT port duplexer 116, and further includes: the signal source analysis module 132 coupled to the DT port duplexer 102 is configured to perform channel-by-channel testing on a signal and lock a signal source, and may specifically include a signal source testing unit, a signal source locking unit, and a frequency point obtaining unit, where the signal source testing unit and the signal source locking unit are respectively connected to a signal source selecting unit in the intelligent control module 133, and the frequency point obtaining unit is respectively connected to the signal source locking unit and a frequency point setting unit of the intelligent control module 133; the signal source analysis module 132 and the DT duplexer 102 may be connected by a coupler 134, but is not limited to this manner, for example, a coupling interface may be disposed on the DT duplexer 102, and the signal source analysis module 132 is directly connected to the corresponding coupling interface, when the implementation is specific, the signal source analysis module 132 may be implemented by an a/D conversion element, a Si4220 downlink receiver and an ADSP-BF 561SBBCZ-5A microprocessor connected to the a/D conversion element, the intelligent digital wireless repeater of the present invention may further be externally connected to a donor antenna 101 and a cover antenna 117, where the donor antenna 101 is connected to the DT duplexer 102, and the cover antenna 117 is connected to the MT duplexer 116;
the intelligent control module 133 is connected with the information source analysis module 132, and is used for controlling the information source analysis module, the digital processing module, and a donor antenna and a coverage antenna externally connected to the repeater, and specifically comprises an information source selection unit and a frequency point setting unit; in particular implementations, the intelligent control module 133 may be implemented by an MPC880CVR133 processor;
the digital processing module is connected between the DT-end duplexer and the MT-end duplexer and is mutually connected with the intelligent control module and used for transmitting and processing signals in a downlink and/or an uplink;
the signal source selecting unit selects a signal source according to signal source information obtained by channel-by-channel testing of a received signal source testing unit on a signal of a specified frequency band, and sends a signal source locking instruction to the signal source locking unit, after the signal source locking unit locks the signal source, the frequency point obtaining unit obtains frequency point information of all channels of the signal source and uploads the frequency point information to the frequency point setting unit, and the frequency point setting unit sets the received frequency point information to the digital processing module.
According to the scheme of the invention, the information (including the frequency point number of the broadcast channel, the cell identification code, the location area identification code, the signal-to-noise ratio, the telephone traffic and the like) of all the information sources in the area where the repeater is located is obtained by carrying out channel-by-channel test on the signals of the appointed frequency band, then the proper cell information source is selected according to the obtained information, and the information source is locked. The problem that the information source is difficult to select is effectively solved, and functions of information source testing, information source selection and the like are realized.
And a digital processing module connected between the DT side duplexer 102 and the MT side duplexer 116 and interconnected with the intelligent control module 133, for transmitting and processing signals in downlink and/or uplink, the digital processing module including a downlink digital processing module and an uplink digital processing module. In particular, both the downlink digital processing module and the uplink digital processing module may be implemented by FPGAs or other programmable logic devices.
As shown in fig. 3, the digital processing module includes a downlink digital processing module and an uplink digital processing module; wherein,
the downlink digital processing module comprises a downlink input filter, a downlink gain adjustable amplifier, a downlink down-conversion mixer, a downlink input intermediate frequency filter, a downlink intermediate frequency amplifier and a downlink A/D converter which are connected in sequence, a downlink channel processor, a downlink D/A converter, a downlink intermediate frequency filter, a downlink up-conversion mixer, a downlink filter, a downlink output adjustable gain amplifier and a downlink output power amplifier; the downlink input filter is connected with the coupler 134, and the downlink output power amplifier is connected with the MT end duplexer;
the uplink digital processing module comprises an uplink input filter, an uplink gain adjustable amplifier, an uplink down-conversion frequency mixer, an uplink input intermediate frequency filter, an uplink intermediate frequency amplifier, an uplink A/D converter, an uplink channel processor, an uplink D/A converter, an uplink intermediate frequency filter, an uplink up-conversion frequency mixer, an uplink filter, an uplink output gain adjustable amplifier and an uplink output power amplifier which are connected in sequence; the uplink input filter is connected with the MT end duplexer 116, and the uplink output power amplifier is connected with the DT end duplexer 102;
the downlink down-conversion mixer, the downlink up-conversion mixer, the uplink down-conversion mixer and the uplink up-conversion mixer are respectively connected with the frequency synthesizer 131;
the DT-end duplexer 102 integrates a low noise amplifier at a downlink input end; the MT end duplexer 116 integrates an uplink input end low noise amplifier;
the information source analysis module also comprises a first judgment unit for judging whether the frequency point acquired by the frequency point acquisition unit changes;
the intelligent control module also comprises a frequency point updating unit;
the first judgment unit is respectively connected with the frequency point acquisition unit and the frequency point updating unit, the frequency point updating unit is connected with the frequency point setting unit, when the judgment result of the first judgment unit is yes, the frequency point updating unit updates the frequency point and transmits the updated frequency point information to the frequency point setting unit, and the frequency point setting unit sets the updated frequency point to the digital processing module, so that the information source frequency point tracking function is effectively realized.
The digital wireless repeater can realize the functions of information source testing, information source selection and information source frequency point tracking, isolation detection and self-excitation offset, uplink noise suppression, self-adaptive repeater gain adjustment and electric regulation of a donor antenna and a coverage antenna. The specific process by which the above-described functions are implemented will be described in detail below.
(1) Information source testing, information source selecting and information source frequency point tracking functions
The information source analysis module 132 is coupled with the base station signal amplified by the downlink low noise, performs channel-by-channel test on the signal of the designated frequency band, and acquires information (including a frequency point number of a broadcast channel, a cell identification code, a location area identification code, a signal-to-noise ratio, a telephone traffic and the like) of all information sources in the area where the repeater is located by analyzing information of a broadcast channel and a control channel on each frequency point; the source parsing module 132 transmits all the acquired information to the intelligent control module 133. The intelligent control module 133 selects a suitable cell information source according to the acquired information, and notifies the information source analysis module 132 to lock on the information source, and the information source locking unit realizes information source locking.
The information source analysis module 132 locks the information source, acquires the frequency points of all channels of the designated frequency band, and reports the frequency points to the intelligent control module 133, and the intelligent control module 133 sets the frequency points of all channels of the designated frequency band in the digital processing module, thereby realizing the functions of automatic selection of the information source and automatic setting of the frequency points.
If the frequency point of the locked cell changes, the information source analysis module 132 will report to the intelligent control module 133 in time, and the frequency point updating and setting unit will update and set the frequency point in real time.
(2) Isolation detection and self-excitation cancellation
A base station downlink signal is received by the donor antenna 101, amplified by the DT duplexer 102, the downlink input filter 103, and the downlink gain adjustable amplifier 104, and then enters the downlink down-conversion mixer 105, the downlink down-conversion mixer 105 converts the base station downlink signal to an intermediate frequency, filtered by the downlink input intermediate frequency filter 106, amplified by the downlink intermediate frequency amplifier 107, and then analog-to-digital converted by the downlink a/D converter 108, and the downlink intermediate frequency analog signal is converted into a digital signal and then processed by the downlink channel processor 109.
The downlink channel processor 109 processes the downlink intermediate frequency digital signals through an adaptive algorithm, picks up useful input signals transmitted by the base station and feedback signals transmitted by the coverage antenna 117 received by the donor antenna 101, and adaptively cancels useless feedback signals in the digital domain, thereby achieving the purpose of eliminating self-excitation.
Meanwhile, the downlink channel processor 109 calculates the relationship between the feedback signal and the useful input signal according to the power strength of the cancelled feedback signal, and obtains the antenna isolation between the donor antenna 101 and the coverage antenna 117 by combining the gain of the downlink.
Typically, after being processed by the downlink channel processor 109, when the antenna isolation between the donor antenna 101 and the coverage antenna 117 is 15dB greater than the gain, the wireless repeater system can stably and reliably operate; when detecting that the difference between the antenna isolation and the gain is smaller than 15dB, the downlink channel processor 109 reports the isolation to the intelligent control module 133, and the intelligent control module 133 controls the gain-adjustable amplifiers, such as the downlink gain-adjustable amplifier 104 and the downlink output gain-adjustable amplifier 114, to increase or decrease the system gain, so that the difference between the antenna isolation and the gain is larger than 15dB.
The downlink if digital signal processed by the downlink channel processor 109 is converted into an analog signal by the downlink D/a converter 110, filtered by the downlink if filter 111, up-converted by the downlink up-conversion mixer 112, filtered by the downlink filter 113, amplified by the downlink output adjustable gain amplifier 114 and the downlink output power amplifier 115, passed through the MT-side integrated duplexer, and transmitted by the cover antenna 117.
The processing of the uplink signal, and the self-excitation cancellation and self-excitation cancellation functions are completely consistent with those of the downlink signal, and are not described herein again.
(3) Uplink noise suppression function
The overlay antenna 117 receives an uplink signal transmitted by a mobile phone, and the uplink signal is filtered by an uplink input filter 118, amplified by an uplink gain adjustable amplifier 119, down-converted by an uplink down-conversion mixer 120, filtered by an uplink input intermediate frequency filter 121, and amplified by an uplink intermediate frequency amplifier 122, and an uplink a/D converter 123 performs digital conversion on the uplink analog intermediate frequency signal, and then the uplink analog intermediate frequency signal is delivered to an uplink channel processor 124 for processing. The uplink channel processor 124 performs time slot power calculation on each uplink carrier in the digital domain, and if the time slot power on the carrier is detected to be lower than a specified power threshold, the uplink channel processor 124 turns off the weak power time slot on the carrier, so as to reduce the uplink noise power from the repeater to the base station and eliminate the interference of the repeater to the base station.
(4) Self-adaptive gain adjusting function of repeater
The downlink channel processor 109 detects the power strength of the downlink input signal and reports the detected power strength to the intelligent control module 133, and the intelligent control module is further configured to control the gains of the downlink gain adjustable amplifier 104 and the downlink output adjustable gain amplifier 114 so that the downlink output power and the gain meet predetermined requirements; specifically, the power strength detection unit of the downlink channel processor 109 detects the power strength of the downlink input signal and reports the detected power strength to the intelligent control module 133, the intelligent control module 133 controls the gain of the downlink gain adjustable amplifier 104 to make the radio frequency front end of the downlink reach the optimal dynamic gain distribution state, and meanwhile, the intelligent control module 133 adjusts the gain of the downlink output adjustable gain amplifier 114 according to the gain of the downlink gain adjustable amplifier 104 and the total downlink output power required by the repeater, so that the downlink output power and the gain of the device reach the specified requirements.
The intelligent control module is also used for controlling the gains of the uplink gain adjustable amplifier and the uplink output adjustable gain amplifier to enable the uplink output power and the gain to meet the preset requirements. Specifically, the power strength detecting unit of the uplink channel processor 124 detects the power strength of the uplink input signal and reports the detected power strength to the intelligent control module 133, the intelligent control module 133 controls the gain of the uplink gain adjustable amplifier 119 to make the uplink radio frequency front end reach the optimal dynamic gain distribution state, and meanwhile, the intelligent control module 133 adjusts the gain of the uplink output adjustable gain amplifier 129 according to the gain of the uplink gain adjustable amplifier 119 and the total uplink output power required by the repeater to make the uplink output power and gain of the device reach the specified requirements.
(5) Electric tuning function of repeater externally connected with donor antenna and coverage antenna
The donor antenna and the cover antenna are electrically tunable antennas, and the electrically tunable antennas can reduce call loss and interference. Meanwhile, the electrically tunable antenna allows the system to adjust the inclination angle without stopping the operation of the repeater, so that the adjustment effect is monitored in real time, and the stepping precision of the adjustment of the inclination angle is higher (0.1 degree), thereby realizing fine adjustment of the network.
The information source analysis module 132 calculates the power and channel quality of each channel in the process of scanning all channels in the space and sends the obtained information to the intelligent control module 133, and after the intelligent control module 133 performs comparison calculation, the intelligent control module 133 controls the horizontal tilt angle and the vertical tilt angle of the donor antenna 101 until the information source analysis module 132 receives the strongest required signal and the best signal quality, and at this time, the judgment module 101 is aligned to the base station; after the donor antenna 101 is adjusted, the downlink channel processor 109 obtains the information of the isolation between the donor antenna 101 and the coverage antenna 117 at this time, and reports the information to the intelligent control module 133, and the intelligent control module 133 controls the coverage antenna 117 to adjust within the specified range of the horizontal tilt angle and the vertical tilt angle, so that the isolation between the donor antenna 101 and the coverage antenna 117 reaches the maximum value. Through the steps, the self-adaptive adjustment of the donor antenna 101 and the self-adaptive adjustment of the coverage antenna 107 are realized, so that the repeater can obtain the optimal information source and the optimal isolation.
Compared with the prior art, the invention has the following advantages and beneficial effects:
the invention solves the practical application problems that the information source is difficult to select, the system is easy to self-excite, the base station uplink is interfered, the power cannot be released, the repeater station cannot adaptively respond after the frequency of the base station is changed, and the like.
The above-described embodiments of the present invention do not limit the scope of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.