ES2363149B2 - REMOTE STATION, SYSTEM AND METHOD OF MONITORING OF ENVIRONMENTAL ELECTROMAGNETIC FIELD IN REAL TIME. - Google Patents

Abstract

Compact and fixed remote station for permanent control and monitoring in broadband of the electromagnetic field in urban environments, in real time and controlled from a remote control center via Intranet / Internet. It is formed by four subsystems; the first two allow the recording and the capture of the signal in real values, in all the frequency bands admitted, in a range between 100 MHz and 6 GHz, for each instant of time, as well as the registration and pre-processing of the same. The third subsystem is responsible for the storage and processing of information, for subsequent forwarding to the remote control center. The last subsystem is constituted by a remote control and storage center that will allow the processing of the information for the presentation of the results in the appropriate format.

Description

Remote station, real-time environmental electromagnetic field monitoring system and method.

Field of the Invention

The present invention relates to equipment and a method for measuring electromagnetic radiation levels and their frequency characterization through a network of fixed broadband monitoring stations (100 MHz-6 GHz).

Background of the invention

The constant development of new technologies and the communication society is causing a considerable increase both in the number of stations, and in the level of power of radio emissions. These increases occur both in licensed band and in free band, where it is even more difficult to exhaustively control the power levels to which it is transmitted.

Additionally, the ignorance of the characteristics and location of the radio stations, because the location location maps are not always available, is an extra impediment that makes real knowledge of the variations in the levels of Field in urban environments.

For all these reasons, a more rigorous control of radio emissions and the location of the stations is necessary, with the municipal entities responsible for ensuring that such control is carried out in a correct, useful and real way. The emitting stations have contracted a power (below the safety threshold), so they must emit complying with these limits; however, there are times when this threshold is exceeded, emitting a higher power in a timely manner. These peak emissions are masked, since the regulations require that the temporary average of measurement (6 minutes) be kept below thresholds, so that emissions that can far exceed the limits, if they are short in time, go unnoticed for current monitoring systems.

Specifically, according to Art. 8 7d of Royal Decree 1066/2001 of Spanish legislation, current regulations require that emissions be kept below thresholds that are established a priori, with the measures collected averaged over six-minute periods.

As already mentioned, this type of measure is not sufficient to objectively assess that exposure limits are met at all times, or to estimate the interaction of electromagnetic fields on an area of the population, since the intensity peaks they are masked by the temporal averaging of the signal. In such a way that a punctual emission during a short period of time, that exceeds the required threshold, goes unnoticed when performing the temporary averaging of the intensity levels in six minutes if the rest has abundant signal valleys.

Current magnetic field monitoring systems record the signals, average the value temporarily, and compare this average value with a certain threshold, corresponding to a frequency band. In such a way that the majority of commercial systems for environmental monitoring of the electromagnetic field (WaveControl: SMRF system; Satimo RF Safety: Insite Box 80; Gigahertz: High frequency measurement with selective fi ltering) and mobile field level measurement equipment ( Rohde & Schwarz, Narda, Satimo

or Wavecontrol) do not allow real-time monitoring and recording of peak power values captured at a given location, differentiated by service and frequency.

Thus, the need is born to characterize and control in a correct and useful way the radioelectric emissions by means of a system that allows to measure the peak intensities of the electromagnetic field, in every moment of time (being able to be considered real time), and that allows to realize differentiated registration for narrower frequency bands than those set by the regulations.

The telemetry stations mentioned above perform power density readings in broadband 24 hours a day, 365 days a year, with a temporal resolution of around 1 minute, by an isotropic sensor or by a triaxial probe. These measures are basic measures of power levels and quality of mobile phone services: GSM 900, GSM 1800 and UMTS. However, the temporary resolution of one minute is excessive to be able to perform a real-time control, so if you want to do studies for every moment of time, this resolution of the detection system must be considerably reduced.

Communication between the stations that make up the system and the control center is usually carried out by mobile technology: GSM, GPRS or UMTS modem controlled by microprocessor. The capture and registration system is interrupted during the time the modem is turned on and the duration of the temporary window for sending data, so that the corresponding measures for that interval are lost. Additionally, the wireless data transmission mechanism itself to the control center introduces environmental electromagnetic pollution, so that a desirable feature for an environmental monitoring system would be that the data recording was not interrupted at any time, and that the system of sending data to the control center did not involve an increase in radiation.

The aforementioned industrial solutions have been deployed in various municipalities in Spain, such as Valencia, Barcelona or Murcia, among others, where a citizen access portal for the visualization of registered historical data is integrated, with a period of daily refreshment of the data , and offering graphs with the specific levels of power density and quality of service, as well as with the average values obtained over time intervals.

Some similar inventions for the detection of ambient electromagnetic fields in broadband are based on mobile devices of indirect measurement, including an optical detector sensitive to electromagnetic radiation (US 7209613) capable of measuring the amount of energy absorbed by various sensors . This type of measurement method is not very accurate, does not have a good frequency resolution and does not allow continuous and real-time recording of electromagnetic field levels.

Another type of fixed remote electromagnetic monitoring stations employ a threshold comparator with the result of the time multiplexing of the outputs given by the set of three orthogonal radiating elements for independent registration (patent ES2273928-T3). These stations are selectively sensitive in at least two bands of electromagnetic field frequencies. The measure is based on a broadband average compared to a threshold limit per radiofrequency service. The system has GSM mobile communication interfaces and serial communication via RS-232 for communication with a central control unit. They also have a data processing and storage unit for those field levels that exceed the pre-set threshold. Therefore, this system is not sensitive to more than two frequency bands, it does not store all the detected field values (but only those that exceed certain set limits), and the field values are not recorded and monitored in real time so automatic

Analyzing all the aforementioned antecedents, a system is designed to replace the perceived deficiencies in the existing environmental monitoring systems, through a network of sensors deployed by the geography of the municipality of origin of the study, which measure the intensity of the electromagnetic field at every moment of time. emitted by the different emission sources of the environment, in real time, for each of the 30 kHz bands into which the working spectrum is divided (from 100 MHz to 6GHz), collecting a total of 236,000 data every 1.6 seconds, so that there is an effective measure that ensures that the thresholds set by the regulations are not exceeded at any time.

With the present invention, this signal collection and processing system allows the generation of real radio maps for every moment of time. So the radioelectric levels of the municipality can be monitored in a spatial manner, generating radio maps for the entire municipality at every moment of time; as well as temporarily, tracking each of the zones.

Additionally, the system has a mobile measurement system that allows movement to areas where it is detected that the limits are being exceeded, and allows the location of the transmitting antenna that violates the regulations for the determined frequency.

Description of the invention

The invention relates to a compact and fixed-location remote station with permanent control and monitoring in broadband of the electromagnetic field in an urban environment 24 hours a day, controlled from a control center via Intranet / Internet.

The present invention has, therefore, been designed to provide a solution that satisfies all the aforementioned needs and that addresses the deficiencies of other environmental monitoring systems by means of a number of features, since the system of the present invention:

•

It realizes the capture, the storage and the monitoring of the electromagnetic field intensity in absolute value (not by means of averaging), for all the instants of time, so it can be subsequently processed as if it were real-time information, and with a resolution Temporary up to 1.6 s.

•

It works in a wide range of working frequencies, ranging from 100 MHz to 6 GHz, a band that includes most of the radio broadcasts characteristic of the urban environment: digital terrestrial television, FM radio, WIFI access points, base stations of GSM and UMTS mobile telephony, WiMax, point-to-point connections on proprietary or free frequencies.

•

Registers the electromagnetic field strength for each of the 30 kHz subbands into which each of the 500 MHz input bands is divided, so that a high frequency resolution is obtained.

•

It performs scanning and scanning of the frequencies sequentially and automatically, so that, every 1.6 s, the entire frequency range is scanned, 236000 samples are collected and the detection is automatically restarted in the first window (from 100 MHz to 500 MHz) , without eliminating any data collected.

•

It makes a continuous recording of the electromagnetic field power density, in which the sending to the central processing block is done after the sweep of the entire frequency range.

•

Send the information via broadband or narrowband cable, depending on the location of the remote station and its characteristics.

•

It reduces the length of the mast to a maximum height of 1.5 meters (since the antennas are placed on a cylindrical central core), allowing the physical separation of the antennas and facilitating that they do not fit together.

•

It has a GPS synchronization system, which allows the system to be synchronized temporarily with the satellite system.

•

Collect the results on radio maps and through historical graphs that show the variations in intensity of the signal collected in absolute values, without averaging them, and with an automatic refresh.

The system consists of four subsystems:

•

A) Local acquisition or detection subsystem (1).

•

B) Monitoring and continuous recording subsystem (2).

•

C) Processing and communications subsystem (3).

•

D) Remote control, display and storage subsystem (4).

The first two subsystems allow the recording of the signals in the manner specified above and allow the capture of the signal in all the frequency bands admitted for each instant of time, as well as the recording and pre-processing of the same. The processing and communications subsystem is responsible for the storage and processing of information, for subsequent forwarding to the remote control center through the communications subsystem. The last subsystem is constituted by a remote control and storage center that will allow the processing of the information for the presentation of the results in the appropriate format.

Brief description of the drawings

A series of drawings that help to better understand the invention and that expressly relate to an embodiment of said invention which is presented as a non-limiting example thereof is described very briefly below.

Figure 1 shows a diagram of the operation of the remote station, with the inputs and outputs of which it consists.

Figure 2 shows the front view of the antenna used in the remote monitoring station.

Figure 3 shows the top view of the electronic device associated with the antenna and located at its base.

Figure 4 shows a scheme of the monitoring and continuous recording subsystem (2).

Figure 5 shows a scheme of the processing and communications subsystem (3).

Detailed description of the invention

The present invention relates to a compact, fixed-location remote station for detecting and reporting electromagnetic field levels in its environment in a frequency range between 100 MHz and 6 GHz, which includes most radio emissions characteristics of the urban environment: digital terrestrial television, FM radio, WiFi access points, GSM and UMTS mobile phone base stations, WiMax, point-to-point connections on proprietary or free frequencies. After each sweep of the frequency band, the information collected by the antennas is processed and stored in the memory of the central processing unit where it is encapsulated and sent to the remote control center.

The system is formed, as shown in Figure 1, by four subsystems:

A) Local acquisition or detection subsystem (1).

B) Monitoring and continuous recording subsystem (2).

C) Processing and communications subsystem (3).

D) Remote control, display and storage subsystem (4).

Each of the components is detailed below.

A) Local acquisition or detection subsystem (1)

This subsystem consists of an antenna of its own development, formed by twelve integrated omnidirectional probes, placed on a cylindrical core, which automatically and sequentially adjust the different central reception frequencies. The working frequency range of the system is set between 100 MHz and 6 GHz. In this broadband range, most of the radio emissions of the urban environment are included: television, radio, mobile telephony, dedicated radio links, among others .

As shown in Figure 2, the measurement of the electromagnetic field level of the environment of each remote monitoring station is carried out by means of a grouping of integrated omnidirectional antennas (21) of their own development, where they are automatically and sequentially adjusted. different central reception frequencies by varying the lambda parameter of the antennas, with a channel width of 500 MHz and a central reception frequency, defined as the median value of the window in question. The SMA connectors allow 6 GHz to be reached, even allowing higher frequency signals to be captured.

Each of the antennas has a different length depending on the lambda parameter that allows to capture the signal from one of the 500 MHz frequency bands into which the working frequency range is divided. Each antenna (21 ’) of the antenna group (21) has a LNA (low noise amplifier) specific to its working band.

The channels obtained are the following:

one.

100 MHz-500 MHz

2.

500 MHz-1000 MHz

3.

1000 MHz-1500 MHz

Four.

1500 MHz-2000 MHz

5.

2000 MHz-2500 MHz

6.

2500 MHz-3000 MHz

7.

3000 MHz-3500 MHz

8.

3500 MHz-4000 MHz

9.

4000 MHz-4500 MHz

10.

4500 MHz-5000 MHz

eleven.

5000 MHz-5500 MHz

12.

5500 MHz-6000 MHz.

These frequency bands will be later fragmented, in modules external to the antenna, in narrow bandwidth channels, 30 kHz and optionally, in 300 kHz channels. The measurements of the level of the surrounding electromagnetic field will be carried out at the central frequency of each of the narrow channels into which each 500 MHz primary channel is divided. In this way the measurements are carried out by means of a fine scan and fine scanning of the spectrum. , analyzing electromagnetic pollution in detail.

The twelve antennas (21 ’) that form the antenna group (21) of the local acquisition or detection subsystem

(1) they are placed on a cylindrical central core (28) (see Figure 3) that allows to reduce the length of the mast to a maximum height of 1.5 meters, allowing the physical separation of the antennas and facilitating that they do not fit together.

Each antenna is responsible for:

-

The automatic and sequential capture of the power levels in each of the 500 MHz frequency bands into which the input frequency range is divided. The antenna's own control module (23) selects the frequency band to be scanned in the feedback module using either a 485 or TTL type communication.

-

The sending of the RF signal (25) and the data (27) to the monitoring and continuous recording subsystem (2), external antenna system, located at the base of the antenna array (21). For the automatic control of the antennas there is an associated electronic device, an antenna selector (22), which is responsible for selecting the antenna that is measured at any time by a switch, capable of governing four antennas at the same time, and that turns off or turn on each of them depending on the frequency band to be measured within the sequential band scan, and thus giving way to the orders coming from the antenna control module (23). From the antenna selector (22) the output signal (25) of the antenna is obtained for treatment in the monitoring and recording subsystem (2). A signal (27) is output from the antenna control module (23) that contains the captured data and is also sent to the external subsystem (2) for processing.

In the central control and communications module of the antenna, different (in this case five) communication interfaces on coaxial cable are distinguished, with which the antenna control module communicates with the different elements and the reception module is interconnected with the data processing, storage and sending system to the control center.

Additionally, in a preferred embodiment, the antenna integrates a GPS module (24) to obtain the precise time and time necessary to identify each record in time of the environmental electromagnetic field values measured by the antenna. Said signal (location and time signal (26)) is sent to the antenna control and the external signal processing system. This time will be common to all the equipment that will make up the complete system, since they use the precision of the Cesio watches of the GPS satellite system.

Figure 3 schematically shows the top view of the electronic device associated with the antenna and located at the base of the antenna, inside an insulating housing. The antenna selector (22) comprises, in the preferred embodiment of Figure 3, three radio frequency switches (29), each in charge of controlling a group of four different antennas (21 '), turning off or on each of the antennas. depending on the orders of the control module (23).

The central core of the receiving device is composed of an SMA coaxial cable input connector, and a three-input RF switch that carries the radio frequency signals of each four-channel branch to said SMA connector.

The antenna has power via a 485 and / or TTL type data and power connection, so that the 9 volt signal and the supply voltage circulate parallel to the coaxial cable, offering a secure and robust broadband connection , up to 10 Mbps of bandwidth that allows a transmission distance of the order of 50 meters. And, in the case of a power connection plus data, TTL that allows a transmission distance of less than 5 meters.

The central control system is powered by 9 volts, using this voltage in two voltage regulators of 5 and 3.3 volts in continuous:

•

The first one, the 5 volt, controls the on and off of the electronic elements of the circuit, so that in each frequency window only the antenna, the circuit components and the integrated integrated low noise amplifier (LNA) are active , while the rest of the antennas do not receive power and do not interfere with the capture of the signal. The synchronization function in the connection and disconnection of the switch and the appropriate LNA is carried out by a microcontroller.

•

The second 3.3-volt regulator feeds a microcontroller that regulates the sequential window jump process and, therefore, is in charge of sending orders for the control of the elements of the antenna system involved in synchronization and de fi nition. of the time window for activation and deactivation of duration for each of the frequency bands, switches and amplifiers, as previously mentioned.

In the central control and communications module of the antenna, five communication interfaces on coaxial cable are distinguished:

one.

The first is that of the antenna, of the recorded signal.

2.

The second is the synchronization input of the GPS device.

3.

The third is composed of four communication cables with the microcontroller, located at the base of the antenna, and which carries out the selection of the corresponding antenna.

Four.

The fourth is the direct connection of power signals at 9 volts and digital control signals at 5 volts.

5.

The fifth corresponds to the coaxial cable output of the signal received from each of the 12 available antennas, and which allow it to be taken to the subsequent processing, processing, storage and communications stage.

B) Monitoring and continuous recording subsystem (2)

This subsystem is responsible for dividing the input bands into smaller sub-bands in which the field measurements will be made, and is formed, as shown in Figure 4, by the following blocks:

I.

Input signal fi ltering module (7): First block of the subsystem that receives the signals from the antenna group (21) of the local acquisition or detection subsystem (1). The signals from the antennas reach a switch, which also receives the autocalibration signal. Using a new switch, the appropriate fi lters are selected, according to the frequency band corresponding to the antenna from which the signal arrives. Thus, this stage is where the different bands into which the working frequency spectrum is divided sequentially with a fixed bandwidth of the 500 MHz bandwidth are sequentially selected.

II.

Amplifier module or low noise amplifier (8): The signals already fi ltered in their frequency band require a stage of amplification in low noise, by means of an LNA amplifier, since the input signals are extremely small, and the differentiation must be differentiated. best possible noise to maintain an adequate signal to noise ratio, making the dynamic range of the information signal sufficient for further processing, and no errors are introduced due to the masking of the noise signal.

III.

Selection module (9): Synchronized stage by clock to turn on and off the previous devices, and to control which channels are active at any time. It is a stage via connecting cable that links the fi ltering and ampli fi cation stage with the processing stage.

IV.

Automatic and sequential frequency selection module f2 (10), dividing the input into 30 kHz bands, with central frequency f2: Responsible for performing the indirect frequency synthesis formed by a set of seven phase tracking loops, PLL (controlled by the DSP (17)), plus an additional control and interconnection with the central monitoring device. The latter PLL provides the internally generated reference signal, for loop control (PLL phase tracking loop) and to obtain a stable output signal, based on that reference. With this configuration of PLLs, and their characteristics (which can register 150,000 values per second), the band can be divided into 30 kHz channels, and the entire input band (100 MHz-6 GHz) can be traversed in 1.6 s , and recording a total of 236,000 samples in each scan. It is, therefore, this stage responsible for dividing the input frequency band into 30 kHz channels, whose central output frequency f2 is sequentially varying at the output of the PLL subsystem to perform the scanner of the working frequency range and being at this frequency at which the level of environmental electromagnetic pollution is measured. The frequency scanner is sequential and automatic, so at the end of each scan in the last window, corresponding to 6 GHz, it will restart the detection in the first window, the one corresponding to the range of 100 MHz to 500 MHz. This module It has calibration inputs, which come from the DSP, to allow the measurements to be adapted according to the external conditions.

V.

Variable digital attenuation and detection module (11): At the output of the PLL a variable digital attenuator is placed behind an ampli fi er to be able to measure the output signal of each PLL with a back-field meter. This meter measures with what power each PLL comes out, and this power is adjusted with the DSP to standardize them and ensure that in the next stage, that of heterodyne, the output is stable.

SAW.

Initial mixing module (12): In the mixing stage, the output obtained is equal to the sum of the contributions from the antenna and the reference of the phase tracking loops, which are stable, in the form f1 + f2, where the frequency f1 corresponds to the frequency of the previous stage, and f2 is a fixed 915 MHz. The signal is then amplified and fi ltered by a bandpass filter that has preset characteristics, with a configuration of the pass band that eliminates spurious lateral components. The fi ltered output signal is directed to the next mixing stage.

VII.

Intermediate mixing module (13): In the intermediate mixing stage, the previously fi ltered signal is heterodyned with a frequency of 10.7 MHz, and subsequent amplification and filtering is performed.

VIII.

Final mixing module (14): In this final mixing stage, the fi ltered signal is heterodyned with a frequency of 4.55 KHz and subsequent amplification and filtering is performed, so that at this point there is already a 30 kHz channel .

IX.

Power detector (15): This is a detector that measures the signal strength of the 30 kHz channel. It is a detector that converts an input radio frequency signal into a logarithmic output scaled in decibels that represents the RSSI parameter. The different values in each scan time are those that are registered, processed, stored and sent to the control and monitoring system in real time. A logarithmic detector with high bandwidth, low noise, high precision and temperature stability, and stable dynamic range up to 8 GHz is used. This detector uses a cascade amplifier chain, obtaining high stability and sensitivity.

X. A / D and D / A converters (16): Two stages of conversion are differentiated. The output A / D converter performs analog to digital conversion at the output, that is, it digitizes the output of the logarithmic detector and takes it to the DSP (17) for processing and sending to the remote control center. The digital to analog conversion is the same as the calibration inputs of the different modules that make up the core of the system, as is the case of the logarithmic detector. These inputs will be used in a first phase of calibration and commissioning.

XI Processing device (17): Data processing means (e.g. a DSP) for the control and synchronization of all stages and of the process of acquisition, preprocessing and sending of data to the processing module through the integrated communication interfaces. You can have communication ports (18 ’) and calibration input / output ports (18). The DSP has an RS485 port that communicates with the processing module connected to the device, through a 10 Mbps channel.

In the continuous monitoring and recording subsystem (2) a reference signal generator for synchronism and a stable power supply are also present.

C) Processing and communications subsystem (3)

This subsystem communicates with the DSP (17) and is responsible for the processing of the information and the sending of data, for which it consists of the following elements and characteristics:

I. Information storage: The information detected by the antennas and processed by the system is stored in the memory of this central processing unit. Each entry in memory consists of at least four basic fields: the antenna identifier, the analyzed radio channel and the capture frequency, the received power density, and the date and time of the capture, with an accuracy of milliseconds. As a security mechanism, the system has a storage of records in non-volatile internal memory, with the ability to store up to 6 days of records, in case of communications drop.

II. Information encapsulation: The system output information, previously digitized, must be packaged for shipment to the control center through the relevant communication interface. To do this, after each frequency scan, from 100 MHz to 6 GHz, the information that has been stored in the processor's memory is encapsulated, with a header that includes the station identifier, and is available for sending via of the system communications interface. The basic frame consists of the following fields: identifier of the remote station (from 0 to 10,000), GPS coordinates (longitude and latitude in decimal), height of the station (in meters), detection frequency (from 100 MHz to 6 GHz), power density (in logarithmic units or dBm), date and time of registration (accuracy of milliseconds), forward error correction sequence, FEC (normally 4 bytes).

III. Communications interface: The information is compressed before sending it, and the data is sent via Intranet / Internet via ADSL to a control center, sequentially, and after each complete scan of the working frequency band. The interface and the means of communication used vary depending on the location of the remote station and its characteristics, and may be broadband cable communications.

IV.

Transmission medium between supervision station and control center: Whenever possible, a broadband connection is established for communication between the supervision stations and the control center. In this way a secure and reliable transmission is obtained and no interference source associated with the broadcast of the remote station itself is introduced.

V.

Remote access: The computer control system has been designed for direct integration into the Internet, allowing an authorized user to control the stations from any point with an Internet connection through the use of secure point-to-point communication tunnels.

D) Control, display and remote storage subsystem (4)

This subsystem refers to the remote control center, which is the nerve center of the network of monitoring stations. A master / slave type star network architecture is established in which the control center is the system master and can send orders to any station in the synchronous (or programmed) network or asynchronously upon request. The control system consists of a storage subsystem of the information collected in the frames that arrive through the communications interface. This system is managed by a database engine, which allows you to keep a historical record of all the values received from the different stations.

The results are collected in radio maps and historical graphs, in which the variations in the intensity of the signal collected in absolute values appear, without averaging them, and with automatic refresh every time new data arrives. The control system consists of a display and control subsystem based on a software application that runs on a server or PC and allows:

-

Visualize the results sent by the remote stations on radiological maps with automatic temporary refreshment.

-

Visualize the data stored in historical graphs with automatic time refresh and the closest to real time, and with the inclusion of statistical values associated with the graphic display time range (minimum, maximum, average value, value of the cursors).

-

Interact with remote stations through remote control. Send orders and slogans. Reconfigure the monitoring station. Restart the station. Send requests to force the sending of the data stored in the internal buffer of the station in case of communications drop.

The method of measuring electromagnetic radiation levels and their frequency characterization is carried out through a network of fixed broadband monitoring stations described above, and by means of a continuous processing, monitoring and recording subsystem, which could be summarized in the following stages:

1st Automatic antenna selection and signal capture by each of the 12 antennas sequentially and automatically for each of the 500 MHz bands of bandwidth into which the input frequency range is divided.

2º The antennas, through the associated electronics, carry out the selection of the work bands for the sequential and automatic processing of the field level values collected in real time by activating and deactivating the appropriate devices at each instant of weather.

3rd Pre-processed signal captured by synchronizing and dating information (through information provided by GPS). 4th Treatment and processing of the detected field values. The following actions are carried out:

-

Automatic and sequential selection of frequencies within each band, in turn dividing the bands into sub-bands of 30 kHz.

-

Calibration of the detected signals.

-

Mixing, ampli fi cation and filtering for sequential selection of 30 kHz bands within each 500 MHz input channel.

-

Logarithmic Detection Conversion of values from electrical units to valid engineering units for field level measurement.

-

Digitization of the analog output signals of the previous stage.

-

Encapsulation and processing of the data by the processing unit, with fields intended to include station identifiers, measurement frequency, measured value, unit position, date and time and error control, among others.

-

Sending the data to the remote control center (4) for final storage and processing.

Claims (12)

1. Remote real-time environmental electromagnetic field monitoring station, characterized in that it comprises:

-

a local acquisition or detection subsystem (1) of the power density as a function of frequency, which has:

•

a grouping of omnidirectional antennas (21), the antennas (21 ') being of the grouping of different lengths, associated with different values of the lambda parameter, and responsible for the continuous collection of the environmental electromagnetic field signal in different frequency bands of job;

•

an antenna selector (22) responsible for selecting, by means of at least one radiofrequency switch (29), the active antenna (21 ’) that measures the electromagnetic field signal at any time;

•

a control module (23) configured to, by controlling the antenna selector (22), perform a sequential scan of the working frequency bands;

•

a GPS module (24) for obtaining the precise time and time necessary to identify each record in time of the environmental electromagnetic field values measured by the antenna.

-

a monitoring and continuous recording subsystem (2), which has:

•

a fi ltered module (7) of the input signal from the local acquisition or detection subsystem (1), filtering said signal sequentially according to the different working frequency bands;

•

a low noise ampli fi cation module (8) to amplify the fi ltered signal;

•

a synchronized selection module (9) for the control of the active channels;

•

an automatic and sequential frequency selection module f2 (10), comprising a plurality of phase tracking loops responsible for sequentially selecting specific frequencies f2 within each of the working frequency bands of the input signal, sequentially dividing the working frequency band of the input signal in subbands with central frequency f2, said frequency f2 at which the level of ambient electromagnetic field is measured;

•

a variable digital attenuation and detection module (11) responsible for measuring the PLL output signals and you would adjust to standardize them;

•

a mixing subsystem comprising at least one mixing module (12, 13, 14);

•

a power detector (15) for converting the radio frequency signal from the output of the mixing subsystem into decibels;

•

an A / D converter (16) to digitize the analog output signals of the power detector (15);

•

data processing means (17) responsible for controlling the automatic and sequential frequency selection module f2 (10), synchronizing the stages, receiving the digital signal from the A / D converter (16), and sending them to the subsystem of processing and communications (3).

2.

Remote real-time environmental electromagnetic field monitoring station according to claim 1, wherein the subbands have an amplitude of 30 kHz.

3.

Remote station for real-time environmental electromagnetic field monitoring according to any of the preceding claims, wherein the monitoring is carried out in a frequency range between 100 MHz and 6 GHz.

Four.

Remote real-time environmental electromagnetic field monitoring station according to any of the preceding claims, wherein the antennas (21 ') of the antenna array (21) are of different length with the variable lambda parameter, with a central frequency and a width 500 MHz channel

5.

Remote real-time environmental electromagnetic field monitoring station according to any of the preceding claims, wherein the grouping of antennas (21) comprises twelve omnidirectional antennas placed on a cylindrical central core (28).

6.

Remote real-time environmental electromagnetic field monitoring station according to any one of the preceding claims, wherein the data processing means comprise a digital signal processor, DSP (17).

7.

Remote real-time environmental electromagnetic field monitoring station according to any one of the preceding claims, further comprising a processing and communications subsystem (3), responsible for storing the pre-processed electromagnetic field values, for processing the information correctly for its subsequent forwarding to at least one remote control center.

8.

Remote real-time environmental electromagnetic field monitoring station according to any of the preceding claims, further comprising a remote control, visualization and storage subsystem (4) that allows the station control remotely, from at least one control center located in a different location than the station.

9.

Real-time environmental electromagnetic field monitoring system, comprising at least one remote real-time environmental electromagnetic field monitoring station according to any of claims 1 to 8, and a remote control center responsible for receiving, both from the less a remote station, as of several, the information relative to the power density of the measured environmental electromagnetic field.

10.

Real-time environmental electromagnetic field monitoring system according to the preceding claim, wherein the remote control center is configured to remotely control the remote station.

eleven.

Real-time environmental electromagnetic field monitoring method, carried out through at least one remote real-time environmental electromagnetic field monitoring station according to any of claims 1-8, characterized in that it comprises:

-

an automatic antenna selection and signal collection stage by each of the antennas (21 ') of a group of omnidirectional antennas (21) that allow the signal to be captured sequentially and automatically in different working frequency bands ;

-

a step of selecting the work bands for sequential and automatic processing of the field level values collected in real time;

-

a preprocessing stage of the signal captured in the central processing unit of the antenna cluster (21) by synchronizing and dating the information;

-

a stage of processing and processing of the detected field values, which comprises:

•

automatic and sequential selection of frequencies within each band, dividing the bands into subbands with a predetermined frequency width;

•

calibration of the detected signals;

•

mixing, amplification and filtering;

•

signal strength detection for each channel;

•

digitalization of the analog output signals of the previous power detection stage;

•

encapsulation and processing of data for sending to a control center (4) through a communication interface.

SPANISH OFFICE OF THE PATENTS AND BRAND Application no .: 201001656 SPAIN Date of submission of the application: 12-30-2010 Priority Date: REPORT ON THE STATE OF THE TECHNIQUE 51 Int. Cl.: G01R29 / 08 (2006.01) RELEVANT DOCUMENTS

Category

Documents cited Claims Affected

To

EP 1542027 A1 (ANTENNESSA et al.) 06.15.2005, paragraphs [30-66]; figures. EP 1233273 A2 (TELECOM ITALIA LAB SPA) 21.08.2002, description; figures. 1-11 1-11

Category of the documents cited X: of particular relevance Y: of particular relevance combined with other / s of the same category A: reflects the state of the art O: refers to unwritten disclosure P: published between the priority date and the date of priority submission of the application E: previous document, but published after the date of submission of the application

This report has been prepared • for all claims • for claims no:

Date of realization of the report 08.07.2011

Examiner E. Pina Martínez Page 1/4

REPORT OF THE STATE OF THE TECHNIQUE Application number: 201001656 Minimum documentation searched (classification system followed by classification symbols) G01R Electronic databases consulted during the search (name of the database and, if possible, terms of search used) INVENES, EPODOC, WPI State of the Art Report Page 2/4  WRITTEN OPINION Application number: 201001656 Date of Written Opinion: 08.07.2011 Statement

Novelty (Art. 6.1 LP 11/1986)

Claims Claims 1-11 IF NOT

Inventive activity (Art. 8.1 LP11 / 1986)

Claims Claims 1-11 IF NOT

The application is considered to comply with the industrial application requirement. This requirement was evaluated during the formal and technical examination phase of the application (Article 31.2 Law 11/1986).  Opinion Base.- This opinion has been made on the basis of the patent application as published. State of the Art Report Page 3/4  WRITTEN OPINION Application number: 201001656 1. Documents considered.- The documents belonging to the state of the art taken into consideration for the realization of this opinion are listed below.

Document

Publication or Identification Number publication date

D01

EP 1542027 A1 (ANTENNESSA et al.) 06.15.2005

2. Statement motivated according to articles 29.6 and 29.7 of the Regulations for the execution of Law 11/1986, of March 20, on Patents on novelty and inventive activity; quotes and explanations in support of this statement D01 is considered the prior art document closest to the object of the invention. However, this document does not affect the novelty and inventive activity of the claims, since it presents substantial differences with the object thereof. Document D01 describes a device for measuring ambient electromagnetic radiation, which comprises the following elements: a detection module (102) composed of a plurality of antennas (103) associated with different frequency bands in the range between 10 MHz and 6 GHz. a module (104) of selective frequency filtering and amplification responsible for separating the frequency bands corresponding to the telecommunication service under study. a transformation module (106) intended to generate continuous signals based on the measured radiation power for each frequency band. a signal processing module (108) for further analysis and data storage. The essential difference between the device of document D01 and the remote station of claim 1 of the application is that in the latter the measurement is made over the entire spectrum of interest (100 MHz-6 GHz) and not only over the range of frequencies associated with a certain service (eg GSM) as in D01, and in very narrow frequency bands. This fact together with the fact that the mode of measurement in the device of the request implies the sequential selection in frequencies and the cyclical repetition of the measurement, leads to a high level of continuity in the same, which constitutes a novel solution and inventive to the technical problem posed related to the difficulty of detecting emissions exceeding the limits, which occur in a short period of time. Thus, both the claimed remote station (claims 1-8) and the monitoring system comprising it (claims 9-10) and the associated monitoring method (claim 11) are considered new and inventive. Consequently, claims 1-11 satisfy the requirements of novelty and inventive activity set forth in Articles 6.1 and 8.1, respectively, of Patent Law 11/86. In conclusion, the application satisfies the patentability requirements established in Art. 4.1 of Patent Law 11/86. State of the Art Report Page 4/4