AU692898B2

AU692898B2 - Mobile radio transmitting/receiving device with transmitting power regulation circuit

Info

Publication number: AU692898B2
Application number: AU29750/95A
Authority: AU
Inventors: Rolf Biedermann
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 1994-07-25
Filing date: 1995-07-19
Publication date: 1998-06-18
Anticipated expiration: 2015-07-19
Also published as: CA2195860A1; ATE185223T1; CN1093343C; DE4426255A1; WO1996003812A1; DE59506960D1; EP0772920A1; DE4426255C2; ES2138222T3; JPH09507984A; FI970264A0; FI970264A; EP0772920B1; AU2975095A; CN1154185A

Abstract

In order to reduce the power consumed by mobile radio transmitting/receiving devices (PT1, PT2) and thus increase their maximum possible duration of operation, the device-specific transmitting power is automatically regulated depending on special information (FSW, A-CRC, X-CRC), such as field intensity values (FSW) and transmission error values (A-CRC, X-CRC), received and acquired by the mobile radio transmitting/receiving device. The mobile radio transmitting/receiving device (PT1, PT2) has for that purpose a sequential control circuit (RK), in which the value of the controlled variables (here the device-specific transmitting power) follows the changing value of the command variable (here the received and acquired special information).

Description

~s MOBILE RADIO TRANSMITTING/RADIO RECEIVING DEVICE, IN PARTICULAR THE MOBILE UNIT OF A CORDLESS TELEPHONE BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a mobile radio transmitting /radio receiving device, in particular the mobile unit of a cordless telephone.

Description of the Related Art Mobile radio transmitting/receiving devices are used in wireless telecommunication as terminals in a wireless telecommunication system. Wireless telecommunication systems currently available on the market are, for example, cordless, mobile-radio, satellite-radio, trunked mobile-radio telephones etc. The mobile radio transmitting/radio receiving devices of the wireless telecommunication systems have in common device-specific and -individual voltage supply units, from which the devices obtain the electrical energy necessary for telecommunication operation.

Voltage supply units used are, for example, batteries, chargeable accumulators etc.

The power or energy consumption of the individual wireless telecommnunication systems is essentially determined by the type of wireless telecommunication, which is specified by different ranges in the transmission of radio messages. Owing to the smaller ":transmission range, the power or energy consumption is much less in the case of cordless telephones conforming to the DECT standard with a transmission range of 25 about 250 m (Digital European Cordless Telecommunication; cf. the publications (1) Nachrichtentechnik Elektronik 42 (Jan./Feb. 1992), No. 1, Berlin; U.-Pilger; "Struktur *des DECT-Standards" [Structure of the DECT standard]; pages 23 to 29; Philips Telecommunication Review: "DECT, Universal Cordless Access System"; Vol. 49, No. 3, 09/1991, pages 68 to 73) than in the case of cellular mobile radio telephones 30 conforming to the GSM standard with transmission ranges of about 2 to 15 km (Groupe Sp6ciale Mobile or global systems for mobile communication; cf. the publication Informatik Spektrum, Springer Vcrlag, Berlin, year 14, 1991, No. 3, pages 137 to 152, "Der GSM-Standard Grundlage fOr digitale europiische Mobilfunknetze" [The GSM standard basis for digital European mobile radio networks]). For example, the transmitting power in the case of DECT-specific cordless telephones is about 250 mW [N:U.IBE101403;VXF L I~IPM (cf. the publications European Telecommunication Standard final draft prETS 300 175-2, 5/1992, part 2, Chapter 5 and Annexe A.2, ETS-Institute 06921 Sofia Antipoles, France), while in the case of mobile radio telephones about 2000 mW are required.

Figure 1 shows the basic structural design of a DECT-specific cordless mobile unit PT1 (Portable Termination). Cordless mobile units of such a structural design have been introduced onto the market under the product designation "Gigaset 952" (cf.

the publications German journal: Funkschau 12/1993, pages 24 and 25; "Digitale Freiheit Gigaset 952: Das erste DECT-Telefon" [Digital freedom Gigaset 952: The first DECT telephone]; author: G. Weckwert 1993). The structural design of the cordless mobile unit is also known, furthermore, from the German journal: Funkschau 10/1993; pages 74 to 77; title: "Digital kommunizieren mit DECT DECT- Chipsatz von Philips" [Digitally communicate with DECT DECT chip set from Philips]; author: Dr J. Nieder and published international patent application WO 94/10812 (Figure 1 with the associated description).

The cordless mobile unit PT1 is assigned to a cordless base station FT (Fixed Termination) via a first radio channel FK1. The cordless base station FT may, for example, be further connected internally via a second radio channel FK2 to a further cordless mobile unit PT2 and externally via a telephone line FSL to a public or private exchange VA. While the cordless mobile unit PT2 is identical in construction to the S. cordless mobile unit PT1, the cordless base station FT, based on published international patent application WO 94/10812 (Figure 1 with the associated description), is constructed according to the representation in Figure 2.

In the case of DECT-specific cordless telephones, the base station FT may be 25 assigned up to 12 mobile units PT. The electrical energy for the cordless telecommunication with the S S

S

IN:LIBE101403:VXF 3 cordless base station FT is obtained by the cordless mobile unit PT1 from a voltage supply unit SVE assigned to the mobile unit PT1. This voltage supply unit SVE essentially comprises an accumulator, which is charged at a charging station in the power-down mode of the cordless mobile unit PT1 and can, furthermore, be exchanged if need be. The voltage supply unit SVE serves here in particular as an energy source for the transmitting power, with which the cordless mobile unit PT1 transmits radio messages to the cordless base station FT. These radio messages are subsequently passed on by the base station FT on the basis of the internal connection to the mobile unit PT2 or on the basis of the external connection as a line message to the exchange VA. The radio message is in this case generally transmitted with a transmitting power of about 250 mW.

In order that the mobile-unit-individual radio messages to be transmitted are also transmitted with this transmitting power, the cordless mobile unit PT1 has a microcontroller MIC and a burst-mode controller BMC, which are connected to each other. While the microcontroller MIC is connected to the voltage supply unit SVE, the burst-mode controller BMC has in the transmitting direction a connection to a radio unit FKT of the mobile unit PT1. In the receiving direction, the cordless mobile unit PT1 is capable, on account of a field intensity measurement device FSME arranged between the radio unit FKT and the burst-mode controller BMC, of acquiring and evaluating field intensity values FSW inherently contained in the reception message.

Furthermore, transmission errors, so-called CRC values (Cycle Redundancy Check; A-CRC, X-CRC; cf. in this PuaI, cQrt-ion respect European Telecommunication Standard Final Draft prETS 300 175-3, 5/1992, Part 3, Chapters 6.2.5 and 10.8.1, ETS Institute 06921 Sofia Antipoles, France), can be detected and evaluated in the burst-mode controller BMC. The evaluation of the field intensity values FSW and of the transmission error values A-CRC, X-CRC -4takes place in the microcontroller MIC. Thus, these values are used, for example, according to the published international patent application WO 94/10764 as an "Antenna Diversity" criterion or according to WO 94/10769 as a criterion for muting the radio transmitting/radio receiving device (mute function).

In order to increase the maximum duration of operation of the cordless mobile unit PT1 with an unchanged voltage supply unit SVE, i.e. an unchanged size and energy capacity of the accumulator, according to EP-O the published international patent application 330 166B1 power excesses in radio systems are avoided by regulating the transmitting power in dependence on the transmission quality and the 1o reception field intensity. This takes place by a combination of a reception level assessment and a quality assessment in a base station of the mobile radio system based on the phase jitter determined from the signal arriving in the base station being used as control criteria for regulating the transmitting power of a mobile handset of a mobile radio system by performing the transmitting power regulation below a specific ol o 15 reception level, predetermined as a set value, on the basis of the control criterion of the quality of the received signal and switching over the transmitting power regulation above a specific reception level to the control criterion of the reception level and making the transmitter of the mobile handset reduce or increase the transmitting power o' if the phase jitter or the reception level exceeds or falls below a predetermined set value. A disadvantage in the case of this type of transmitting power regulation is that the transmitting power of the mobile handset can be regulated only with the support of the base station of the mobile radio system.

SUMMARY OF THE INVENTION An object underlying the invention is to enrich the prior art in a mobile radio transmitting and/or radio receiving device, in particular a mobile unit of a cordless telephone, to the extent that both the known disadvantage is ameliorated and the power consumption of the mobile radio transmitting/radio receiving device is reduced and consequently the maximum possible duration of operation of the device is increased.

In accordance with one aspect of the present invention, there is provided a mobile radio transmitting/radio receiving device, comprising: first means for receiving a radio message transmitted on a radio link between a transmitter and the mobile transmitting/receiving device, second means for acquiring special information contained in the radio message, said special information including specific characteristics associated with said radio message, third means for setting a transmitting power level associated with said device, and, IN:\LIBE101403:jIp fourth means for controlling said specific transmitting power through said third means, in dependence on said special information.

The mobile radio transmitting/radio receiving device may be designed for example as the mobile unit of a cordless telephone or as the mobile handset of a mobile telephone, the device-specific transmitting power is automatically regulated in dependence on special information, for example field intensity values and/or transmission error values, received and acquired in the mobile radio transmitting/radio receiving device. For using the mobile radio transmitting/radio receiving device as the mobile handset of a mobile radio system, data relating to the transmitting power of the mobile radio transmitter are additionally required and are preferably contained in the special information. For regulating the transmitting power, the mobile radio transmitting/radio receiving device has a sequential control circuit, in which the value of the controlled variable (here the device-specific transmitting power) follows the changing value of the command variable (here the received and acquired special "to: 15 information).

o BRIEF DESCRIPTION OF TIE DRAWINGS 0 0 Figure 1 is a schematic block diagram of a cordless mobile phone system as known and showing details of the mobile unit; Figure 2 is a schematic block diagram of a cordless mobile phone system as known and showing details of the fixed unit; and Figure 3 is a schematic block diagram of a cordless mobile phone system showing details of the mobile unit according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An exemplary embodiment of the invention is explained with reference to S. Figure 3.

Figure 3 shows on the basis of Figure 1 the cordless mobile unit PT1 being modified for the purposes of this embodiment of the invention. The modification of the cordless mobile unit PT1 consists in that the microcontroller MIC of the mobile unit PT1 is assigned a control circuit RK, which is formed by individual program modules assigned to the microcontroller MIC. With this control circuit RK, the field intensity values FSW and transmission error values A-CRC and X-CRC available in the microcontroller MIC are used and evaluated for regulating the transmitting power of the mobile unit PT1. The control circuit is in this case preferably designed as a sequential control circuit, in which the value of the controlled variable (here the transmitting power to be regulated) follows the changing value of the command variable (here the field intensity values FSW and transmission error values A-CRC and X-CRC IN;\LIBE)01403:jj I I 0 -6are the command variables) (cf. in this respect DIN 19226, May 1968 edition, "Regelungstechnik und Steuerungstechnik Begriffe und Benennungen" [Control engineering definitions and terms], Chapters 9 and 10, pages 17 to The field intensity values FSW can be used to derive a distance from the cordless base station FT, while the transmission error values A-CRC, X-CRC can be used to determine a measure of the quality of the received radio messages. After this evaluation, the controlled reduction or increase in the transmitting power is initiated in the radio unit FKT by the micro-controller MIC via I/O ports or registers, which may be assigned for example to the burst-mode controller BMC. The regulation may in this case take place both continuously and in just a few large increments (discontinuously).

Furthermore, it is possible to perform the regulation as a two-step control or a multistep control.

The control circuit RK described above for regulating the transmitting power of the cordless mobile unit PT1 may alternatively also be used in the mobile handsets of mobile radio systems. For the regulation referred to above it is then necessary, however, for the command variable additionally to contain data relating to the transmitting power of the mobile radio transmitting device. This is necessary because, in contrast to cordless telephones, in the case of mobile radio telephones the respective transmitting device no longer transmits with a constant transmitting power.

20 Although other modifications and changes may be suggested by those skilled in the art, it is the intention of the inventor to embody within the patent warranted hereon all changes and modifications as reasonably and properly come within the scope of his contribution to the art.

[N:\tLIE101403;VXF

Claims

1. A mobile radio transmitting/receiving device, comprising: first means for receiving a radio message transmitted on a radio link between a transmitter and said mobile transmitting/receiving device, second means for acquiring special information contained in the radio message, said special information including specific characteristics associated with said radio message, third means for setting a transmitting power level associated with said device, 1o and fourth means for controlling said specific transmitting power, through said third means, in dependence on said special information.

2. A mobile radio transmitting/radio receiving device as claimed in claim 15 1, wherein said fourth means includes a sequential control circuit. o 2

3. A mobile radio transmitting/radio receiving device as claimed in claim 2, wherein said sequential control circuit includes an automatic control circuit. 20

4. A mobile radio transmitting/radio receiving device as claimed in claim 2, wherein said sequential control circuit includes means for regulating said :transmitting power, time-continuously.

A mobile radio transmitting/radio receiving device as claimed in claim 25 2, wherein said sequential control circuit includes means for regulating said transmitting power, time-discontinuously. 0000

6. A mobile radio transmitting/radio receiving device as claimed in claim 2, wherein said sequential control circuit is operable to regulate said transmitting power with respect to an upper and lower limit value.

7. A mobile radio transmitting/radio receiving device as claimed in claim 1, further comprising means for assigning measurable field intensity values to said special information inherently contained in the radio message.

8. A mobile radio transmitting/radio receiving device as claimed in claim 1, further comprising means for assigning transmission error values to said special information inherently contained in the radio message. [n:\libE]O 1400:jjp I i 1 -8-

9. The device as claimed in any one of claims 1 to 8, wherein the radio message transmitted between the transmitter and the device is composed in conformity with the DECT standard.

10. The device as claimed in any one of claims 1 to 8, wherein the radio message transmitted between the transmitter and the device is composed in conformity with the GSM standard and the data relating to the transmitting power of the transmitter are additionally assigned to the special information inherently contained in the radio message.

11. A mobile radio transmitting/radio receiving device, substantially as described herein with reference to Fig. 3. DATED this Thirtieth Day of October 1997 Siemens Aktiengesellschaft Patent Attorneys for the Applicant SPRUSON FERGUSON se 9 o Sd 0* 555 e [n:\libE]01400:VXF -I i I Abstract In the case of mobile radio transmitting/radio receiving devices (PT1, PT2), in order to reduce the power consumption of the mobile radio transmitting/radio receiving device (PT1, PT2) and consequently increase the maximum possible duration of operation of the device, the device-specific transmitting power is automatically regulated in dependence on special information (FSW, A- CRC, X-CRC), for example field intensity values (FSW), transmission error values (A-CRC, X-CRC), received and acquired in the mobile radio tzansmitting/radio receiving device. The mobile radio transmitting/radio receiving device (PT1, PT2) has for this purpose a sequential control circuit in which the value of the con- trolled variable (here the device-specific transmitting power) follows the changing value of the command variable (here the received and acquired special information).