Method of generating a frequency-hopping sequence for radio communication, as well as radio facility and radio communication system therefor
First Claim
1. A method of generating a frequency-hopping sequence containing data on carrier frequencies to be allocated for radio communication between radio facilities which change between the allocated carrier frequencies at regular intervals, said method comprising the steps of:
- determining input data which specify at least a number of available carrier frequencies and a frequency-hopping scheme to be used; and
generating the frequency-hopping sequence from the input data using an algorithm according to which data on a carrier frequency to be allocated are calculated for each time interval by combining the input data and by accessing a lookup table containing a pseudorandom association of input values with output values for scrambling intermediate results produced by the algorithm in a pseudorandom fashion, characterized in that several different lookup tables are accessed, with the intercommunicating radio facilities being assigned the same lookup table.
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Accused Products
Abstract
In a GSM (Global System for Mobile communications) system, a lookup table used to scramble intermediate results in a pseudorandom fashion is also used to uniquely associate radio facilities with one another, particularly to associate mobile stations with a base station. Several different lookup tables (RNTBLi) may be used which are uniquely assigned to the radio facilities, with the intercommunicating radio facilities being assigned the same lookup table. The different lookup tables are preferably generated on the basis of subscriber identifications, whereby each subscriber is assigned a respective one of the lookup tables. The invention is particularly suited for the construction of private radio communication systems
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Citations
10 Claims
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1. A method of generating a frequency-hopping sequence containing data on carrier frequencies to be allocated for radio communication between radio facilities which change between the allocated carrier frequencies at regular intervals, said method comprising the steps of:
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determining input data which specify at least a number of available carrier frequencies and a frequency-hopping scheme to be used; and
generating the frequency-hopping sequence from the input data using an algorithm according to which data on a carrier frequency to be allocated are calculated for each time interval by combining the input data and by accessing a lookup table containing a pseudorandom association of input values with output values for scrambling intermediate results produced by the algorithm in a pseudorandom fashion, characterized in that several different lookup tables are accessed, with the intercommunicating radio facilities being assigned the same lookup table. - View Dependent Claims (2, 3, 4, 5, 6)
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- 7. A radio communication system comprising radio facilities which change between carrier frequencies at regular time intervals in accordance with a frequency-hopping sequence containing data on the carrier frequencies to be allocated, and which comprise means for calculating the frequency-hopping sequence using an algorithm according to which the information on a carrier frequency to be allocated is calculated for each time interval by combining input data specifying at least a number of available carrier frequencies and a frequency-hopping scheme to be used and by accessing a lookup table containing a pseudorandom association of input values with output values for scrambling intermediate results produced by the algorithm in a pseudorandom fashion, characterized in that the means for calculating the frequency-hopping sequence access several different lookup tables, and that those radio facilities which are in radio communication with one another have storage means in which the same lookup table is stored.
- 9. A radio facility within a radio communication system wherein said radio facility and other radio facilities change at regular intervals between carrier frequencies allocated to them according to a frequency-hopping sequence containing data on the carrier frequencies to be allocated, said radio facility and said other radio facilities comprising means for calculating the frequency-hopping sequence using an algorithm according to which data on a carrier frequency to be allocated is calculated for each time interval by combining input data specifying at least a number of available carrier frequencies and a frequency-hopping scheme to be used and by accessing a lookup table which defines a pseudorandom association of input values with output values for scrambling intermediate results produced by the algorithm in a pseudorandom fashion, characterized in that the means for calculating the frequency-hopping sequence access several different lookup tables, and that the radio facility which is in radio communication with one (BS) of the other radio facilities have a storage means in which the same lookup table is stored as in said one other radio facility.
Specification