Radio system

Abstract

A radio system (110) comprising a first (120) and a second (130) radio unit which comprise a transmitter (122, 132) and a receiver (121, 131). The first radio unit (120) communicates with a first external radio unit (101) and the second radio unit (140) with a second external radio unit (102). Both transmitters (122, 132) are arranged to vary their output power level in response to a request from the external radio unit with which they are arranged to communicate. Both of the transmitters also vary their output power level in response to a variation in the transmitter output power level of the other radio unit.

Description

CROSS-REFERENCE TO RELATED APPLICATION

132 121 of the radio unit 120 to an antenna. As is also shown in FIG. 3, the radio unit 120 comprises a control unit 208, which control the function of, inter alia, the receiver 121 and the transmitter 122. Suitably, but not necessarily, the control unit 208 comprises one or more processors, for example a microprocessor. The radio unit 120 also comprises an interface unit 240, which is the interface towards one or more other radio units, in this case the second radio unit 130, for which reason the interface unit is labeled “RU 2 Int”.

It is through the interface unit 240 that the radio unit 120 receives the information described above from the second (or more) radio unit, i.e. the sample of the signals received by the receiver of the second radio unit, as well as requests for increase in the output power level of the transmitter 122 of the second radio unit. In addition, it should be mentioned that the interface unit 240 is “reciprocal”, i.e. signals which are received through the interface unit 240 also correspond to signals which are sent to the second radio unit 130 if the radio system 110 is designed so that the second radio unit 130 can utilize such signals.

As shown in FIG. 3, signals to the cancellation circuit 123 and the transmitter 122 are routed through the control circuit 208. This should be seen as a preferred example only, it is naturally within the scope of the invention is to let the signals be routed in other ways as well, for example to connect them straight to their respective destinations, such as for example, the cancellation circuit 123. The function of the cancellation circuit 123 will not be elaborated upon here, since it has been described above.

As also shown in FIG. 3, the radio unit 120 also comprises a memory unit “Mem” 220. The memory unit is used in order to, for example, let the control unit store data and, if applicable, executable program code.

As explained in connection to FIG. 1, the transmitter 122 is arranged to vary the output power level of its transmissions in response to a request from the external radio unit with which it is arranged to communicate, i.e. the external radio unit 101, and it is also arranged to vary its output power level of its transmissions in response to a variation of the output power in the transmitter of the other radio unit, so that a requested increase in the output power level of one of the transmitters results in an increase in the output power level of both transmitters. It is such increases that are suitably controlled by the control unit 208, by means of, inter alia, the information received by the control unit from the interface unit 240, as well as information comprised in signals received by the “own” receiver 121. Also, if the second radio unit 130 is designed to utilize such information, the control unit 208 transmits requests for an increase (and in some embodiments, decrease, as will be described below) to the second radio unit via the interface unit 240.

Regarding the increase in output power level from the transmitters 122, 132, the following principle is suitably adhered to: if one of the radio units receives a request for an output power increase, the request is met by both transmitters in equal amounts, which is also the requested amount.

In the case that both of the external radio units request an increase during one and the same time period, this is suitably handled by letting the transmitters use the larger requested increase, which is suitably handled by the control units of the two radio units. The time period in question is of course a design parameter which can be varied between different systems, but a suitable range for such time periods is 10-100 msec.

As touched upon previously, in some embodiments of the invention, the radio units are also arranged to let their transmitters decrease their output power level in response to requests for this from the external radio units, in the case that a decrease is requested by all (both, in this case) of the external radio units during the same time period. The time period in question is of course a design parameter which can be varied between different systems, but a suitable range for such time periods is 10-100 msec.

In one such embodiment, the decrease which is carried out by the transmitters 122, 132, of the first 120 and second 130 radio units is the smaller of that requested by the two external radio units, if the requested amounts vary. This is in order to ensure that the path which needs the highest power level has its needs met by the radio system.

Suitably, the requested decrease is carried out by the transmitters 122, 132, of both radio units 120, 140 in equal amounts.

In order to avoid “over-regulation”, in one embodiment the radio units 120, 130, are arranged to ignore requests for increases or decreases in the output power of their transmitters for a defined period of time following an increase or decrease in their output power level. The time period in question is of course a design parameter which can be varied between different systems, but a suitable range for such time periods is 10-100 msec.

FIG. 3 also shows an alternative configuration of the radio unit 120, indicated by means of dashed lines: as shown, the radio unit 120 can comprise an additional interface unit 212, a “ΔP interface”, shown as “ΔP Int.” in FIG. 3. This unit 212 interfaces with a power control unit 214 “ΔP Ctrl” which is common to the radio unit 120 and one or more other radio units in a radio system in which the radio unit 120 is comprised. Thus, in the example shown in FIG. 2, the additional interface unit receives commands for variations, i.e. increases and/or decreases in the output power level. The notation “ΔP” is used here for such variations, in order to show that commands from the control units are suitably given as a “delta”, i.e. relative to a nominal power level which is suitably set when the radio unit 120 is installed, and which is a value which is also stored, suitably in the radio unit, for example in the memory unit 220.

In an embodiment which uses a common power control unit such as the one shown as “ΔP Ctrl” 214 in FIG. 3, requests for variations in the output power level of the transmitter T×1 are suitably received via the receiver R×1 121 and routed to the common power control unit via the interface 212; commands for variations in the output power level of the transmitter unit 122 are then also received from the common power control unit via the interface 212. Also, if a common power control unit is used, it is suitably this unit which handles the logic involved in setting the values for variations in the output power level of the transmitter T×1, as well as the transmitters of the other radio units comprised in the system of the invention, i.e. in the case shown in FIG. 2 the transmitter 132 of the second radio unit 130.

FIG. 4 shows a schematic flow chart of a method 400 of the invention. Steps which are options or alternatives are indicated by means of dashed lines and arrows in FIG. 4.

As shown in FIG. 4 and as has also emerged from the description above, the method 400 of the invention is intended for use in a radio system such as the one 110 of FIGS. 1 and 2, and comprises, box 410, the use of at least a first radio unit in order to communicate with a first external radio unit and a second radio unit in order to communicate with a second external radio unit, with both radio units comprising a transmitter and a receiver.

According to the invention, the method 400 comprises letting the transmitters of both of the radio units vary, box 415 the output power level of their transmissions in response to a request from the external radio unit with which they communicate, and also letting both of the transmitters increase, box 420, the output power level of their transmissions in response to an increase in the transmitter of the other radio unit, so that a requested variation in the output power level of one of the transmitters results in a variation in the output power level of both transmitters.

In one embodiment of the method 400, box 425, if the requested variation ΔP is a request for an increase, the requested increase ΔP is carried out by both transmitters in equal amounts, which is the requested amount.

In one embodiment of the method 400, box 430, the radio units let their transmitter use the larger increase ΔP in the case that both of the external radio units request a variation which is an increase during the same time period.

In one embodiment of the method 400, box 435, the transmitters of both the first and second radio units only carry out a decrease −ΔP in the power level of their transmissions in response to requests for decrease which are requested by both of the external radio units during the same time period, shown as Δt in FIG. 4.

In one embodiment of the method 400, the decrease which is carried out by the transmitters of the first and second radio units is the smaller of that requested by the two external radio units, if the requested amounts vary.

In one embodiment of the method 400, a requested decrease is carried out by the transmitters of both radio units in equal amounts.

In one embodiment of the method 400, the radio units ignore requests for increases or decreases in the output power of their transmitters during a defined period of time following an increase or decrease in their output power level.

In one embodiment of the method 400, at least one of the radio units (120, 130) carries out a cancelling operation in order to cancel interference from the external radio unit with which the other radio unit in the system is arranged to communicate, the canceling being performed by means of receiving samples of the signal received by the other radio unit's receiver as well as the signal received by the own radio unit's receiver.

The invention is not limited to the examples of embodiments described above and shown in the drawings, but may be freely varied within the scope of the appended claims.

Claims

1. A radio system comprising:

at least a first and a second radio unit, both of which radio units comprise a transmitter and a receiver;

the first radio unit arranged to communicate with a first external radio unit and the second radio unit arranged to communicate with a second external radio unit; and

and the transmitters of both the first and the second radio units arranged to vary the output power level respective output power levels of their transmissions in response to a request communication from the external radio unit with which they are arranged to communicate, with both of said transmitters also being arranged to vary the output power level respective output power levels of their transmissions in response to a variation in the output power level of the transmitter of the other of the first and second radio unit, so that a requested variation in the output power level of one of the transmitters results in a variation in the output power level of both transmitters, wherein both radio units are arranged to enable their transmitters to use a larger of an increase in a variation in the output power level specified in a request from both of the first and second external radio units, wherein the request includes the variation which is an increase during the same time period both of said transmitters also being arranged to vary the respective output power levels of their transmissions such that, when a communication from the first external radio unit would cause a first increase value in output power level at the first radio unit in a time period, and a communication from the second external radio unit would cause a second increase value in output power level at the second radio unit during the time period, both the first and the second radio units use a larger of the first increase value and the second increase value to vary the respective output power levels of their transmissions.

2. The radio system of claim 1, wherein said first and second radio units are arranged to enable their transmitters to only carry out a decrease in the power level respective output power levels of their transmissions in response to requests for communications that would cause a decrease which are requested by both of the first and second external radio units during the same time period.

3. The radio system of claim 2, wherein the decrease which is carried out by the transmitters of the first and second radio units is the smaller of that requested by the first and second external radio units, if the requested amounts vary both of said transmitters also being arranged to vary the respective output power levels of their transmissions such that, when the communication from the first external radio unit would cause a first decrease value in output power level at the first radio unit in a time period, and the communication from the second external radio unit would cause a second decrease value in output power level at the second radio unit during the time period, both the first and the second radio units use a smaller of the first decrease value and the second decrease value to vary the respective output power levels of their transmissions.

4. The radio system of claim 3, wherein said requested the decrease in output power level is carried out used by the transmitters of both the first and second radio units in equal amounts.

5. The radio system of claim 1, wherein the first and second radio units are arranged to ignore requests for communications that would cause increases or decreases in the output power of their transmitters during a defined period of time following an increase or decrease in their output power level.

6. The radio system of claim 1, wherein at least one of the first and second radio units is equipped with a cancellation circuit for cancelling interference from the external radio unit with which the other radio unit in the system is arranged to communicate, said cancellation circuit being arranged to perform cancelation by receiving samples of the signals received by the receivers of both the first and second radio units.

7. A method for use in a radio system , system, comprising the use of at least a first radio unit in order to communicate with a first external radio unit and a second radio unit in order to communicate with a second external radio unit, both of said radio units comprising a transmitter and a receiver, the method comprising:

enabling the transmitters of both the first and the second radio units to vary the output power level respective output power levels of their transmissions in response to a request communication from the external radio unit with which they communicate; and enabling both of said transmitters to vary the output power level respective output power levels of their transmissions in response to a variation in the output power level of the transmitter of the other of the first and second radio unit, so that a requested variation in the output power level of one of the transmitters results in a variation in the output power level of both transmitters, wherein both radio units enable their transmitters to use the larger increase in the case that both of the first and second external radio units request a variation which is an increase during the same time period of said transmitters also being arranged to vary the respective output power levels of their transmissions such that, when a communication from the first external radio unit would cause a first increase value in output power level at the first radio unit in a time period, and a communication from the second external radio unit would cause a second increase value in output power level at the second radio unit during the time period, both the first and the second radio units use a larger of the first increase value and the second increase value to vary the respective output power levels of their transmissions.

8. The method of claim 7, wherein the transmitters of both of said first and second radio units only carry out a decrease in the power level respective output power levels of their transmissions in response to requests for communications that would cause a decrease which are requested by both of the first and second external radio units during the same time period.

9. The method of claim 8, wherein the decrease which is carried out by the transmitters of the first and second radio units is the smaller of that requested by the first and second external radio units, if the requested amounts vary, when the communication from the first external radio unit would cause a first decrease value in output power level at the first radio unit in a time period, and the communication from the second external radio unit would cause a second decrease value in output power level at the second radio unit during the time period, both the first and the second radio units use a smaller of the first decrease value and the second decrease value to vary the respective output power levels of their transmissions.

10. The method of claim 9, wherein said requested the decrease in output power level is carried out used by the transmitters of both the first and second radio units in equal amounts.

11. The method of claim 7, wherein the radio units ignore requests for communications that would cause increases or decreases in the respective output power levels of their transmitters during a defined period of time following an increase or decrease in their output power level.

12. The method of claim 7, wherein at least one of the radio units carries out a cancelling operation in order to cancel interference from the external radio unit with which the other radio unit in the system is arranged to communicate, said canceling being performed by receiving samples of the signals received by the receivers of both the first and second radio units.

13. The method radio system of claim 1, wherein the first radio unit's output power level depends on the output power level requests of caused by a communication from the second radio unit, and the second radio unit's output power level depends on the output power level requests of caused by a communication from the first radio unit.

14. The method radio system of claim 1, wherein the variation in the output power level of one of the transmitter transmitters is a requested an increase.

15. The method radio system of claim 14, wherein the requested increase results in an increase in the output power level of both transmitters.

16. The method radio system of claim 1, wherein the first radio unit includes a first interface unit which connects an antenna of the first radio unit to the first radio unit's transmitter and receiver, and wherein the second radio unit includes a second interface unit which connects an antenna of the second radio unit to the second radio unit's transmitter and receiver.

17. The method radio system of claim 16, wherein the first interface unit receives information from the second radio unit that includes samples of signals received by the second radio unit as well as requests for communications that would cause an increase in the output power level of the transmitter of the second radio unit.

18. The method radio system of claim 1, wherein the first radio unit includes a first cancellation circuit and the second radio unit includes a second cancellation circuit.

19. The method radio system of claim 18, wherein the first cancellation circuit receives a signal from the first radio unit and another signal from the second radio unit, wherein a desired output signal of the first cancellation circuit by multiplying the signal received from the second radio unit by a factor “k.”

20. A radio system comprising:

at least a first and a second radio unit, both of which radio units comprise a transmitter and a receiver;

the first radio unit arranged to communicate with a first external radio unit and the second radio unit arranged to communicate with a second external radio unit; and

the transmitters of both the first and the second radio units arranged to vary respective output power levels of their transmissions in response to a communication from the external radio unit with which they are arranged to communicate, with both of said transmitters also being arranged to vary the respective output power levels of their transmissions in response to a variation in the output power level of the transmitter of the other of the first and second radio unit, so that, when a communication from one of the first or the second external radio units would cause a variation in the output power level of the transmitter with which it is arranged to communicate, the variation in the output power level of one of the transmitters results in the variation in the output power level of both transmitters.

21. The radio system of claim 20, wherein both of said transmitters are arranged to vary the respective output power levels of their transmissions, so that, when communications from both the first and the second external radio units would cause variations in the respective output power levels of the radio units with which each of the external radio units are arranged to communicate, the variations in the output power levels of both of the transmitters results in a variation in the output power levels of both transmitters that is dependent on one of the variations that comprises a largest increase in the output power level.

22. The radio system of claim 20, wherein the variations in the respective output power levels of the radio units comprise variations that are an increase during a same time period.

23. A method for use in a radio system, comprising the use of at least a first radio unit in order to communicate with a first external radio unit and a second radio unit in order to communicate with a second external radio unit, both of said radio units comprising a transmitter and a receiver, the method comprising:

enabling the transmitters of both the first and the second radio units to vary respective output power levels of their transmissions in response to a communication from the external radio unit with which they communicate; and

enabling both of said transmitters to vary the respective output power levels of their transmissions in response to a variation in the output power level of the transmitter of the other of the first and second radio unit, so that when a communication from one of the first or the second external radio units would cause a variation in the output power level of the transmitter with which it is arranged to communicate, the variation in the output power level of one of the transmitters results in the variation in the output power level of both transmitters.

24. The method of claim 23, wherein both of said transmitters are arranged to vary the respective output power levels of their transmissions, so that, when communications from both the first and the second external radio units would cause variations in the respective output power levels of the radio units in which each of the external radio units are arranged to communicate, the variations in the output power levels of both of the transmitters results in a variation in the output power levels of both transmitters that is dependent on one of the variations that comprises a largest increase in the output power level.

25. The method of claim 23, wherein the variations in the respective output power levels of the radio units comprise variations that are an increase during a same time period.