Telecommunications – Transmitter and receiver at separate stations – Having measuring – testing – or monitoring of system or part
Reexamination Certificate
1998-01-28
2001-02-13
Nguyen, Lee (Department: 2746)
Telecommunications
Transmitter and receiver at separate stations
Having measuring, testing, or monitoring of system or part
C455S009000, C455S067700, C455S424000, C370S241000, C379S001040, C379S029010
Reexamination Certificate
active
06188876
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to monitoring a system and a method for radio frequency (RF) processing units of a plurality of base stations in a wireless communication network, and, in particular, to a system and a method for remote monitoring spectrums of RF signals of the specific points at RF signal processing units, and controlling radio-frequency processing units of base stations in such networks after comparing the monitored spectrums with standard ones.
2. Brief Description of the Prior Art
The radio frequency(RF) processing unit including RF receiving and transmitting portion is one of the important units of a base station in a wireless communication network. The RF receiving portion comprises a receiving antenna; a low noise amplifier(LNA), which filters and amplifies the RF signal received through a receiving antenna; and a down converter which converts down the received RF signal(100 MHz~10 GHz) to an intermediate frequency(IF) signal(1 MHz~100 MHz). The RF transmitting portion comprises an up converter, which converts up an IF signal to an RF signal; a linear power amplifier(LPA), which amplifies the converted RF signal; and a transmitting antenna. The RF receiving/transmitting portion of base station is composed of analog circuits, so the functional characteristics of the RF signal processing unit gradually deteriorates unlike other units of the base station composed of digital circuits. Because of this gradual deterioration, it is difficult to detect faults or determine the time when an RF signal processing unit is to be replaced.
Technicians have conventionally visited each base station in order to check the functional status of the RF signal processing units by measuring their frequency characteristics with a spectrum analyzer to fix or replace the unit when its spectrum shape has changed from the normal spectrum shape. With such a human monitoring system, it is inconsistent and unreliable to decide about faults, repair time, or the replacement time for the RF signal processing unit; moreover, such a decision depends on the skill of the technician. As demand for high-quality service in wireless communication system demands more base stations, human monitoring system becomes less efficient and economical. Therefore, it becomes necessary to develop a new and effective monitoring systems and methods.
SUMMARY OF THE INVENTION
Accordingly, it is a general object of the present invention to solve the above mentioned problems of the conventional human monitoring system and to provide novel and effective monitoring systems for the RF signal processing units for multiple base stations in a wireless communication network.
A more specific object of the present invention is to provide monitoring methods and systems in which a monitoring unit can remotely monitor and control the RF signal processing units for numerous base stations in a wireless communication network.
Another further specific object of the present invention is to again provide such monitoring methods and systems for numerous base stations wherein data communication between a monitoring unit and a remote control command unit can be performed irrespective of the bandwidth or channel capacity for the link connecting them.
The foregoing objects of the present invention are accomplished by providing the remote monitoring system of the RF signal processing units of the base stations comprising: (1) a feature extraction unit for extracting features representing the functional status of the RF signal processing unit, which is comprised of a selection means for choosing a specified point among the numerous points to be detected, an extraction means for converting down RF signal detected at the chosen point into IF signal, a means for measuring the power spectrum of the intermediate (IF) signal, an A/D converter for digitizing the power spectrum, a transmitter for transmitting the digitized signal of the power spectrum, and a control command processor; (2) a remote monitoring unit comprising a means for evaluating the functional status of the RF signal processing unit based on the power spectrum received from the previously described feature extraction unit, and a controller for sending a control command associated with the result of the evaluation to the control command processor in the feature extraction unit; and (3) a communication link between the feature extraction unit and the remote monitoring unit, wherein the control command processor in the feature extraction unit which performs the command received through the communication link from the controller of the remote monitoring unit.
The present invention is characterized in that the remote monitoring system comprises: (1) a feature extraction unit for extracting features representing the functional status of the RF signal processing unit, which is comprised of a selection means for choosing a point among numerous points to be detected, an extraction means for converting down the RF signal detected at the chosen point into an IF signal whose frequency is low enough to be digitized, an A/D converter for digitizing the IF signal, a memory for storing the digitized signal, a transmitter for transmitting the stored digital signal, and a control command processor; (2) a remote monitoring unit comprising a power spectrum calculator for computing the power spectrum of the real-time digital signal received from the feature extraction unit, an evaluation means for evaluating functional status of the RF signal processing unit based on the computed power spectrum, and a controller for sending a control command associated with the result of the evaluation to the control command processor in the feature extraction unit; and (3) a communication link between the feature extraction unit and the remote monitoring unit.
The present invention is further characterized in that the transmitter of the feature extraction unit transmits the digitized signal stored in the memory through the communication link at transmission rate lower than the rate at which the detected analog signal is digitized.
The present invention is further characterized in that the remote monitoring method of the RF signal processing units of the base stations comprises the steps of: (1) choosing one of the many points to be detected for a RF signal processing unit in a base station; (2) converting down the RF signal detected at the chosen point into an IF signal; (3) measuring the power spectrum of the converted IF signal; (4) converting the power spectrum into digital data; (5) transmitting the digital data representing the power spectrum; (6) evaluating the functional status of the RF signal processing unit based on the transmitted digital data; (7) sending an appropriate control command associated with the result of the evaluation; and (8) executing the control command. In addition, instead of using the step for measuring the power spectrum, the step of computing the power spectrum can be also done between the steps of transmitting and evaluating.
The remote monitoring system according to the present invention remotely monitors and controls the RF signal processing unit of each base station in the following way. The selection means chooses one of the many points to be detected and an extraction means converts down the RF signal detected at the chosen point during a predetermined time into an IF signal. Then the power spectrum of the IF signal is measured by the spectrum measuring means and then the measured spectrum signal is digitized by the A/D converter. The digitized data representing a power spectrum are finally transmitted to the remote monitoring unit by the transmitter through the communication link. The evaluation means of the remote monitoring unit checks the functional status of the RF signal processing unit based on the spectrum data received from the feature extraction unit. According to the result of the evaluation, the controller sends a data, such as commanding to replace the RF module working at present with a redundant RF module, to th
Arent Fox Kintner & Plotkin & Kahn, PLLC
Fine Digital, Inc.
Jama Isaak R.
Nguyen Lee
LandOfFree
System and method for remote monitoring of RF units in base... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with System and method for remote monitoring of RF units in base..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and System and method for remote monitoring of RF units in base... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2580475