GB2523737A - Remedial signal generator - Google Patents

Abstract

This application relates to a device adapted to fit within, or to be positioned adjacent to, a mobile phone, for remedying the potentially harmful effect on humans of RF transmissions. The device includes means for detecting radiation generated by the handset and means for analyzing the radiation. The device receives power from the mobile phones battery and may be located within the battery. When analysis indicates the detected radiation is considered harmful to health the remedial signal generation means is triggered to provide a noise signal to disrupt the potentially harmful effects of the RF transmissions. Such a field is sometimes referred to as a confusion field in the prior art. Preferably the device measures the variation in time of the amplitude of the low frequency envelope of the detected radiation. This may be used to distinguish voice transmissions from data transmissions. Voice transmissions are considered more harmful to health.

Description

REMEDIAL SIGNAL GENERATOR

The present invention relates to methods and apparatus for protecting living systems from potentially adverse effects upon them from electric fields, magnetic fields and electromagnetic fields. The invention is particularly concerned with protection from potentially adverse radiation from modern day battery powered mobile telecommunications handsets which are used for a variety of functions including both voice and data transmission. In particular the invention is concerned with protection when the handset is used in close proximity to the body, in particular the head, as is 0 often the case during voice transmission.

All electromagnetic radiation consists of oscillating electric and magnetic fields and the frequency, which is the number of times per second at which the wave oscillates, determines their properties and the use that can be made of them. Frequencies are measured in hertz or Hz, where 1 Hz is one oscillation per second, 1 kHz a thousand, 1 MHz is a million, and GHz, is a thousand million. Frequencies between 30 KHz and 300 GHz are widely used for telecommunications, including broadcast radio and television, and comprise the radio frequency band.

Cellular mobile services operate at frequencies authorised by governments and typically operate within the frequency ranges 872 -960 MHz, 1710 -1875 MHz and 1920 -2170 MHz. These frequencies are within the microwave frequency band which encompasses the range between 300 MHz and 300 GHz. Other applications within this range include radar, telecommunication links, satellite communications, weather observation and medical diathermy. This invention is particularly useful with devices that operate on frequencies used for cellular telephones.

A radio frequency wave used to carry information in radio communications is referred to as a carrier wave. The radio frequency carrier wave of any system is produced by the transmitter as a sine wave, or other regular waveform. A carrier wave conveys no information if its properties do not vary in time. If the carrier wave is to convey any information, for instance, speech, music or digitized data, this information has to be added to it in some way. The process of varying one or more properties of a carrier signal with respect to the information that it is to carry is known as modulation.

Properties of the carrier wave that may be varied through modulation include for instance, amplitude, frequency, phase or any combination of these. For example, for AM (amplitude modulation) transmission, the electrical signal from a microphone produced by speech or music is used to vary the amplitude of the carrier wave, so that at any instant the size or amplitude of the RE carrier wave is made proportional to the size of the electrical modulating signal. In FM (frequency modulation), the instantaneous frequency of the carrier deviates from the carrier frequency by an amount dependent on the strength of the modulating signal. Phase modulation (PM) is a form of modulation that represents information as variations in the instantaneous phase of a carrier wave. FM and PM are very commonly used for current day radio communications.

A mobile phone (cell phone) sends and receives information (voice messages, text messages, emails, fax, computer data, downloads information etc) by radio communication. Radio frequency signals are transmitted from the phone to the nearest base station and incoming signals (carrying the information from the source to which the phone user is listening) are sent from the base station to the phone at a slightly different frequency. Base stations link mobile phones to the rest of the mobile and fixed phone network. Once the signal reaches a base station it can be transmitted to the main telephone network, usually by an optical fiber network.

Each base station provides radio coverage to a geographical area known as a cell.

Base stations (BS) are connected to one another by a mobile services switching centre (MSC), which tracks calls and transfer them as the caller moves from one cell to the next. An ideal network may be envisaged as consisting of a mesh of hexagonal cells, each with a base station at its centre. The cells overlap at the edges to ensure the mobile phone users always remain within range of the base station. Without sufficient base stations in the right locations, mobile phones will not work. If a person with a mobile phone starts to move out of one cell into another, the controlling network hands over communications to the adjacent base station.

There are conflicting views as to the effects of electric fields, magnetic fields and electromagnetic fields on living systems. However there is considerable evidence that certain fields may be damaging to living systems including humans. It may also be that the detrimental effects are long term and their full impact has not yet been realised.

There has been a dramatic increase around the world in the use of electrically operated devices particularly battery powered hand held mobile telephones. All such devices have associated with them electromagnetic field emissions which, to varying degrees, have the potential to affect human health. Of particular interest are devices that transmit radio frequency (SF) signals and are used in close proximity to the human body particularly the head, for instance hand held cellular phones and other personal communication devices. At issue is the possibility that the safety standards under which these devices are manufactured, which establish RF exposure limits to the users of these devices, may not adequately account for effects below the thermal threshold, that is, at exposure levels well below levels that can produce measureable heating and can be attributed to direct energy transfer. The potential for such low 0 level effects is supported by substantial evidence from epidemiologic studies and laboratory research which suggests that any measures that could reduce and/or minimize the effects of such exposure would be beneficial to the users of these devices. Laboratory research also suggests that the severity of impact from SF exposure at non-thermal levels is dependent on the modulation characteristics of the SF signal, in particular amplitude variations in the low frequency envelope. Signals that display a greater degree of regularity have been shown to have greater biological impact.

Modern mobile devices include a wide range of services which employ complex communication schemes. In the operation of such devices, the modulation characteristics of transmitted SF signals can vary substantially depending on the type of information that is being transmitted, for instance, voice or data. Accordingly, the extent of biological effects can also vary. It is therefore desirable that a remedial system be capable of assessing the nature of the modulation to determine the potential extent of biological impact. Furthermore, such a remedial system should be compact and adaptable for use with different telephone handsets and different battery systems. Additionally it is desirable that the remedial system operates effectively, is only used when required as determined by the emitted radiation and yet consumes little power from the battery to preserve battery life.

United States Patent 5544665 is concerned with the protection of living systems from the harmful effects of electromagnetic fields and states that certain fields have an effect on the enzyme ornithine decarboxylase. The patent states that the potentially damaging effect can be reduced or eliminated if the detrimental electromagnetic field is altered either by switching the field on and off or superimposing an electromagnetic noise field upon it. The patent further states that the effect can only be reduced if such alteration causes relevant characteristic properties of the field to change in time at intervals of less than 5 seconds and preferably at intervals from 0.1 to 1 second.

The characteristic properties that can be changed are said to be frequency, phase, direction, waveform or amplitude. Similar effects are discussed in Bioelectromagnetics 14 395 -403 (1993) and Bioelectromagnetics 18 388 -395 (1997).

United States patent 5544665 dates from 1991 and describes various applications of the bio-protection scheme including applications to cellular telephones of the type available at that time which were bulky and used only for voice transmission. The 0 EMX Corporation has promoted batteries for such cellular telephones that make use of the technology described in United States patent 5544665. When used with a cellular phone, these batteries are said to produce a noise electromagnetic field that is superimposed over the local SF field generated by the operation of the telephone for voice transmission thereby causing the total field to be irregular and thus not likely to cause biological effects. The noise was generated by a coil forming part of the battery pack. Activation of the noise was accomplished by monitoring the flow of electric current from the battery to the phone and using this as an indirect means to determine when the phone was transmitting RE fields that were likely to produce biological effects. This activation technique worked reasonably well with older phones but proved to be unreliable with newer phones that now have many more applications that demand power from the battery but do not produce SF fields. Use of such applications could cause false triggering of the noise and potentially unnecessary and unacceptable reduction in battery life.

In WO 2012/041514 we describe technology that addresses these issues and provides a process, an apparatus and systems for the reduction or elimination of the potentially harmful effect on humans or animal life caused by exposure to electromagnetic fields produced by devices that operate by transmitting SF signals.

The technology comprises a device provided with means to reduce or eliminate the potentially harmful effect of the RE signals and further provided with a means to sense and analyse RE fields and assess their ability to produce biological effects, and which activates the means to reduce or eliminate the potentially harmful effect of the measured SF signals on humans or animal life based on the outcome of that assessment.

The techniques described in WO 2012/041514 prefer to employ the combination of a passive radio frequency detector to monitor the local SF field which wakes up an active radio frequency detector when a potentially harmful bio-effective field is detected. The passive detector would activate (Power on) the remedial device to initiate analysis of a radio frequency signal received by the antenna by means of a remedial control module. This system does not however provide adequate power management for both the required term operation of the device and the detection and analysis of the potentially harmful signal and the generation of the remedial signal.

We have found that particularly when used with modern day battery powered portable telephone handsets with so many functions the constant powering of such 0 an active circuit by the battery can create an undesirable drain on the battery.

Accordingly the present invention provides a design which minimizes power consumption while allowing monitoring of the RF field and providing any remediation that may be required.

Accordingly the invention provides a remedial device for the reduction or elimination of the potentially harmful effect on humans or animal life caused by exposure to electromagnetic fields produced by devices that are battery operated to transmit RF signals containing a module for the detection and analysis of the RF signals wherein said module is powered by the battery of the device and when the presence of potentially harmful radiation is detected the detection module activates a remedial signal generator.

The design minimizes power consumption while still allowing monitoring of the RE field when needed. In the preferred embodiment means are provided to monitor the power drain on the battery and the application conditions are monitored and the maximum power drain is set accordingly. Power drain can be set to be at its lowest when the battery is in storage, somewhat higher when the battery is connected to the phone and battery voltage is above a certain acceptable level, and highest but still as low as possible when RF is being generated and needs to be assessed. In all cases battery voltage is measured and in the last two environments both battery voltage and the RE signal are measured. The power management control may conveniently be implemented by software which is executed within a microcontroller forming part of the remedial device.

According to the present invention, the detection module is configured to measure the low frequency envelope of an SF signal and follow its variation in amplitude over a prescribed interval, preferably of the order of 1 second. Those measurements are

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then analysed to assess the need to turn on the remedial signal. The amplitude variation of the low frequency envelope differs depending on the transmission protocol and the information being transmitted. In general, amplitude variation patterns for voice transmission are different than for data transmission and are characteristic of signals that are more likely to cause biological effects. Furthermore, voice transmission often implies proximity of the handset to the head which also increases the likelihood of biological effects. Therefore, identification of the communication mode can be useful in the determination of potential biological impact. Accordingly, in the present invention the detected signals can be analysed to 0 identify the communication modes and determine the level of the remedial signal. By way of example the analysis can differentiate between GSM voice communication mode, GSM data communication mode, 3G or 4G voice communication mode and 3G or 4G data communication mode. The differentiation is preferably performed by an analytical module within a microcontroller that is programmed to detect the different communication modes.

The remedial signal can then be switched on according to the radiation sensed and the strength of the remedial signal can be tailored to the nature of the radiation that has been sensed. For example, if the remedial signal strength in relation to GSM voice communication is deemed to be 100%, for voice communication for 3G, 50% may be sufficient whereas for 3G data communication 25% may be required. The micro controller can be programmed to cause the remedial signal generator to provide signals of the appropriate strength according to the analysis of the signals received.

The detector is preferably an antenna.

The invention therefore allows the strength of the remedial signal to be tailored according to the nature of the potentially harmful radiation which in turn depends upon the detected mode of operation of the telecommunication handset.

In a preferred embodiment power management is provided using a timer that switches the power supply to a component of the detection module and to the remedial signal module on and off to minimise the power drain from the battery and yet provide active (powered) detection of the potentially harmful signals. The timer should be one that requires a minimal power for operation and is directly connected to the battery. The timer preferably has a wake up interval to preserve battery life and the wake up interval should be sufficiently small to allow analysis of any Radio Frequency signals detected by the antenna so as to determine if there are any harmful signals in time to activate the remedial signal generator.

The present invention minimizes power consumption while still allowing monitoring of the RE field when needed. In the preferred embodiment means are provided to monitor the power drain and the application conditions are monitored and as discussed the power drain is set accordingly. As discussed the power management control may conveniently be implemented by software which is executed within a 0 microcontroller and many functions can be implemented within such a microcontroller. In particular it can monitor parameters such as: -Battery voltage: sourced from circuit that connects to the battery -RF signal. The microcontroller can control Output parameters such as the Power control signals, the Bioprotection noise signal. Additional functions which can be implemented in the software include: -Application state classification and power management, implementation of application state monitoring and control algorithms, Implementation of RF signal classification algorithms Implementation of the remedial bioprotection signal generator.

The invention may be applied to most electronic devices that operate by transmitting RE signals which could be potentially harmful to human or animal life, but it is particularly useful with battery powered personal communication devices, such as cellular telephones, that are used in close proximity to the human body particularly to the head. In a preferred embodiment the invention provides a system that can be readily adapted for use with a variety of mobile phone designs and their associated batteries.

Earlier studies have shown that RF radiation can cause potentially harmful effects if it is regular, meaning that it has constant properties, and is continuously applied for periods of over 10 seconds and that the potential harm can be substantially eliminated if the regularity period is reduced to no more than 1 second. The means to eliminate the potential harm in the present invention may superimpose a noise electromagnetic field on the potentially harmful radiation to produce a combined field that is irregular in time, meaning that it does not have constant properties in time, and therefore no longer has the potential to cause harm. Use of the noise field, which is hereinafter referred to as the remedial signal, is preferred as it allows for use of the electronic device without altering the manner in which it operates.

The invention is particularly useful with battery operated personal communication devices. In the preferred embodiment the potentially harmful effect of the RF radiation is inhibited by a means that generates an appropriate remedial signal that is superimposed on the RF signal to provide a combined signal that is iiregular and therefore has no bio-effecting consequence. Any suitable means may be used but the means may comprise an inductive coil which is activated to produce the remedial 0 signal field, primarily magnetic in nature, employing power from the battery of the cellular telephone.

The means which senses and identifies the potentially harmful radiation may be any standard RE sensor. We prefer to use an antenna, with accompanying electronics, which have been suitably configured to identify the particular radiation which is emitted by the electronic device and which is considered to be potentially harmful.

The antenna is preferably a wire such as a copper wire which can be fitted into any convenient space within an existing telephone handset without requiring any significant modification thereof. Additionally the means may be provided with means to differentiate the nature of the radiation according to the communication mode that is being employed. In order to enhance the selectivity of the device it is preferred to amplify the signal received prior to analysis and accordingly the sensing means includes an amplifier in addition to the preferred antenna.

The system of the invention may be formed to fit within existing cellular phone handsets or other personal communication devices, with little or no modification to the devices. For instance, the component may be such that it may be incorporated inside the handset and maybe in association with the battery pack that provides power to the handset. The preferred system comprises an electronic circuit that comprises an RE antenna, a signal detection module, an analysis module and a remedial signal activation module and a coil for generating the remedial signal field.

The signal detection module, the analysis module and the signal activation module may be implemented using a microcontroller. The coil may be formed around the battery of the handset. Where the battery is lithium polymer, the coil may be physically pressed into the battery, so as to minimize the space needed to fit this part. Alternatively the system may be separate from the battery within the handset, or separate from the handset but adapted to be placed next to the handset while the handset is in use to provide a remedial signal. For example the component may be formed as a card article, of credit card dimensions and shape, with electronics incorporated within the card, and a coil for providing the remedial signal being formed around the edge of the card.

As described the system is preferably managed by a microcontroller which performs the analysis function of the received signal and the control function of the remedial signal. In a preferred embodiment the microcontroller also oversees the operation of the system and can sense the remaining capacity of the battery and transition the 0 system to storage mode minimizing current consumption prior to recharging.

The invention therefore provides more specifically, a remedial device for association with a battery powered personal communication device that emits RE transmissions potentially harmful to humans or animal life, the remedial device including sensor means operated by the battery for sensing the presence of said RE transmissions, signal analysis means for assessing the RE transmissions to determine if they are likely to cause biological effects, and a remedial signal generator means also operated by the battery, said signal analysis means being coupled for actuation of said remedial signal generator means, and the remedial signal generation means being arranged to establish a remedial electromagnetic field in the vicinity of the handset. In a preferred embodiment power management is implemented to conserve battery power. In the preferred embodiment the signal analysis means differentiates between signals generated by voice communication and those generated by other forms of communication such as data communication so as to activate the appropriate remedial signal. In particular the signal analysis can differentiate between signals with different low frequency envelope patterns for example the amplitude and timing, to identify if voice or data is being transmitted which in turn provides an indication of the potential for the radiation to cause harm.

The RE sensor, is preferably an antenna, which has been suitably configured to detect the particular radiation which is emitted by the electronic device and which is considered to be potentially harmful. The antenna may be positioned anywhere within the telephone handset and should be responsive to a carrier wave frequency of the cellular handset that is a microwave frequency in the region of 0.8 to 2 GHz, as detailed below. (As an alternative to a separate antenna, the coil for establishing the remedial field may also be configured to detect RF transmissions.) The SF detection stage, for detecting SF transmissions that may contain potentially harmful components, preferably includes a signal analysis means, which signal analysis means is arranged to make an analysis of the detected RE transmissions in order to make a determination of whether the characteristics of the transmission signal has features that would indicate that it is potentially harmful and activate the remedial signal accordingly. The SF detection stage may be arranged to provide an actuation signal to the signal analysis means. The detection stage is activated by the battery of the handset perhaps through use of a timer and is arranged to monitor SF emissions from the handset, and to rectify and integrate an SF transmission signal.

0 One or more delayed versions of the detected signal are compared with the current version. The amplitude and timing of the detected signal are evaluated in order to determine whether there is SF radiation of significant duration that is likely to cause biological effects. This is typically the case during speech transmission to and from the handset. In this event, a power control signal is generated. Although the detected signal may be of low strength it may still be potentially damaging to health and we prefer to provide an amplifier between the active detector and the analysis module to enable detailed analysis and good use of the signal.

The use of passive (unamplified) an active (amplified) detection module therefore allows for evaluation of the antenna signal over a wide signal range. The output of the passive and active detector modules may then be evaluated using software loaded in the microcontroller which also controls the remedial signal generator. The signal analysis means (software loaded in the microcontroller) examines the amplitude and timing characteristics of the detected signals to determine whether the transmission is voice or data and the likely transmission protocol, for instance, GSM, 3G or other commonly used protocols, and whether the particular type of transmission contains features that would indicate that it is potentially harmful.

The signal analysis means may provide an activation signal to a power control module within the microcontroller to enable supply of power to said remedial signal generator (or selected parts thereof). The remedial control generator may include a remedial signal control module, which provides a control signal to the power source, and a control signal to a remedial signal generator module, for generating the desired form of remedial signal. The remedial signal control module is responsive to an output from the RE detection stage, and is preferably provided within a microcontroller for executing one or more algorithms for controlling the remedial signal generator module. The microcontroller can also implement the power management and the signal analysis activity. As preferred, the control module waits for a period of about 1 second until it receives a continual output from the detection stages, and then requests the power unit to provide power to the generator module, so that the remedial signal is generated for a period of about 3 seconds. The waiting period of about 1 second is significant in that it represents a minimum period in which the presence of an SF signal may trigger a response in living tissue. Any radiation generated by the handset for a period of less than this minimum period is regarded as not requiring remedial action. The period of 3 seconds is chosen on the grounds of convenience, since with a longer period, a remedial field may be generated when it 0 is not required, and a shorter period may result in excessive switching operations within the circuitry. At the end of the 3 second period, the control module is reset unless or until a continual signal is again present from the SF detection stages.

The remedial signal generator module may include a digital noise generator, which is coupled through digital to analog conversion means and filter means, for providing an analog form of the remedial signal, to a coil which provides a means for establishing the remedial field in the neighbourhood of the handset.

The radiation with which this invention is particularly concerned is that emitted by the cellular telephone when it is transmitting or receiving information especially voice information and particularly when it is transmitting voice information as this tends to generate more RE signals and in particular when it is transmifting or receiving speech as that is generally the time when it is in closest proximity to the head, and transmission radiation occurs for a significant length of time so increasing the likelihood of the creation of harmful biological effects.

In operation therefore the cellular telephone will be activated for use and will immediately generate the potentially harmful radiation at the particular predetermined frequency. The presence of the radiation will immediately be sensed and analysed by the sensor and detection means of the invention, which will then activate the remedial signal (noise) generator means that converts the constant potentially harmful radiation to a random benign wave pattern. The sensor and detection means can also detect when the potentially harmful radiation is no longer being generated and deactivate the remedial signal until the next time that it is required. As disclosed in prior art negation of the potentially harmful effect of the radiation generated by use of a cellular telephone can be achieved with a remedial signal having a frequency preferably in the range 30 Hz to 90 Hz.

An important aspect of an embodiment is that the radiation sensor and detector and the generator of the remedial signal can be incorporated into the cellular telephone without the need to alter the structure of the cellular telephone itself. In order to be useful in mobile telephones the remedial device should preferably fit within conventional handsets without requiring modification of the handsets. It is therefore important that the remedial device be miniaturized. Additionally it is important that 0 the device is flexible and readily adaptable so that it can be used in a wide variety of handsets. The remedial device therefore contains a microcontroller which incorporates and directs many of the functions of the remedial device such as the SF signal analyser module and, the remedial signal generator module. Use of such a microcontroller together with a small antenna and a miniaturised remedial signal amplifier provides a miniaturised system useful with a wide range of handsets and with a wide range of batteries. As previously described the antenna may also be compact to fit within existing mobile telephone handsets. A copper wire is particularly useful.

The invention may be used with any of the battery cells used for cellular telephones such as lithium ion batteries but use with the softer batteries such as lithium polymer batteries may be advantageous since the printed circuit board containing the components of this invention and the coil can be pressed into the battery casing to provide a battery with minimal reduction in battery capacity relative to a standard equivalent battery.

Figure 1 hereto is a schematic illustration of the architecture of a remedial signal generator according to the present invention.

The generator comprises a detector for Radio Frequency Signals such as the Antenna (1) which feeds information concerning the signals it detects into the Radio Frequency Front End detector (2) which is powered on instruction from the microcontroller (3) from a power source (4) which is typically the battery of the mobile telephone handset. The signal which may be amplified in the SF Front End then passes to an analogue/digital convertor (5) which may be within the microcontroller (3). The signal is then analysed to determine if it includes potentially harmful radiation and if so the nature of the radiation, the analysis being performed within the microcontroller (3). Based on the nature of the signal analysed the microcontroller passes a signal to actuate the remedial signal generator which consists of a signal implemented within the microcontroller and followed by a low pass filter (7) the output of which typically feeds an audio amplifier (8) and then a bioprotective field coil (6).

All components are powered by the power source (4). In this way the bioprotective remedial field is provided according to the radiation sensed by the antenna with analysis, control and remedial signal generation modules implemented within the microcontroller. The microcontroller may also be provided with means (not shown) for power management including verifying the charge remaining in the power source O and for moving the system to a storage mode when the charge is low and waiting for recharging. in I.,

Claims (17)

1. CLAIMS1. A remedial device for the reduction or elimination of the potentially harmful effect on humans or animal life caused by exposure to electromagnetic fields produced by devices that are battery operated and transmit RF signals containing a module for the detection and analysis of the RF signals wherein said module is powered by the battery of the device and when the presence of potentially harmful radiation is detected the detection activates a remedial signal generator.

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2. 2. A remedial device according to Claim 1 in which the detector module measures the variation in time of the amplitude of the low frequency envelope of the signals produced by the radio frequency detector.
3. 3. A remedial device according to Claim 1 or Claim 2 in which the signals are analysed to differentiate between voice and data transmissions.
4. 4. A remedial device according to Claim 3 which differentiates between voice and data communication modes of GSM, 3G or 4G communication protocols.
5. 5. A remedial device according to Claim 3 or Claim 4 in which the differentiation is performed by a microcontroller that is programmed to detect the different communication modes.
6. 6. A remedial device according to any of the preceding claims wherein the remedial signal is switched on according to the radiation sensed and the strength of the remedial signal is tailored to the nature of the radiation that has been sensed.
7. 7. A remedial device according to any of the preceding claims where the detection module includes an antenna.
8. 8. A remedial device according to any of the preceding claims in which a timer is provided to switch the power supply to the detection module on and off.
9. 9. A remedial device according to claim 8 in which the timer on interval is small enough to preserve battery life while still allowing analysis of Radio Frequency signals in the mobile phone frequency range.
10. 10. A remedial device according to any of the preceding claims comprising an SF antenna, a microcontroller that operates the signal detection module, the analysis module and a remedial signal generation and activation module, and acoil for applying the remedial signal field.
11. 11. A remedial device according to Claim 10 in which the power management of the system is implemented by software with the microcontroller.O
12. 12. A remedial device according to Claim 11 in which the microcontroller implements application state monitoring and control algorithms, RE signal classification algorithms
13. 13. A remedial device according to any of the preceding claims in which the active detection module provides signal amplification.
14. 14. A battery powered personal communication device, such as cellular telephone containing a remedial device according to any of the preceding claims.
15. 15. A mobile telephone according to Claim 14 wherein the remedial device is incorporated inside the handset.
16. 16. A mobile telephone according to Claim 14 or Claim 15 in which the remedial device is in association with the battery pack that provides power to the handset.
17. 17. A battery for a personal communication device containing a remedial device according to any of Claims ito 13.