Radio communication system with multiple and simultaneous encoding technique

Abstract

A method of operating a radio communication system uses a Code Division Multiple Access (CDMA) technique. Multiple scrambling codes may be used in a single cell to alleviate the shortage of channelisation codes available for downlink channels from a primary station. To minimise interference caused by the presence of non-orthogonal signals, signals to a single secondary station may be transmitted as a plurality of parts encoded with different scrambling codes.

1. A method of operating a radio communication system employing a code division multiple access technique, comprising
 a primary station transmitting data to a plurality of secondary stations, 
 the primary station encoding different separate and distinct portions of said data with different scrambling codes after spreading of said data, using at least one of a primary scrambling code and or a secondary scrambling code to encode the separate and distinct portions of said data for transmission to a secondary station, and transmitting a slotted mode signal to the secondary station using a primary scrambling code for a first portion of the data and a secondary scrambling code for the remainder of the data, both portions being transmitted contemporaneously; 
 wherein the data is transmitted in slotted frames and non-slotted frames. 
 
     
     
       2. A The method as claimed in  claim 1 , wherein the majority of the data transmitted by the primary station is encoded with the primary scrambling code and the remainder of the data being encoded with the secondary scrambling code. 
     
     
       3. A The method as claimed in  claim 1 , wherein the primary station transmits a slotted mode signal to the secondary station using the secondary scrambling code. 
     
     
       4. A The method as claimed in  claim 1 , wherein the primary station transmits a multi-code signal comprising a plurality of channels to the secondary station using the primary scrambling code for a first portion of the channels and the secondary scrambling code for the remainder of the channels. 
     
     
       5. A radio communication system employing a code division multiple access technique comprising:
 a primary station and a plurality of secondary stations, 
 the primary station having:
 means for transmission of data to the secondary stations and; 
 means for encoding different separate and distinct portions of said data with different scrambling codes after spreading of said data, and 
 means for using at least one of a primary scrambling code and or a secondary scrambling code to encode the separate and distinct portions of said data for transmission to a secondary station, and means for transmitting a slotted mode signal to the secondary station using the primary scrambling code for a first portion of the data and the secondary scrambling code for the remainder of the data, both portions being transmitted contemporaneously; 
 wherein the data is transmitted in slotted frames and non-slotted frames. 
 
 
     
     
       6. A primary station for use in a radio communication system employing a code division multiple access technique,
 the primary station having:
 means for transmission of data to the secondary stations and; 
 means for encoding different separate and distinct portions of said data with different scrambling codes after spreading of said data, and 
 means for using at least one of a primary scrambling code and or a secondary scrambling code to encode the separate and distinct portions of said data for transmission to a secondary station, and means for transmitting a slotted mode signal to the secondary station using the primary scrambling code for a first portion of the data and the secondary scrambling code for the remainder of the data, both portions being transmitted contemporaneously; 
 wherein the data is transmitted in slotted frames and non-slotted frames. 
 
 
     
     
       7. A The primary station as claimed in  claim 6 , further comprising means for transmitting the majority of the data encoded with the primary scrambling code and the remainder of the data encoded with the secondary scrambling code. 
     
     
       8. A The primary station as claimed in  claim 6 , further comprising means for transmitting a slotted mode signal to the secondary station using the secondary scrambling code. 
     
     
       9. A The primary station as claimed in  claim 6 , further comprising means for transmitting a multi-code signal comprising a plurality of channels to a secondary station using the primary scrambling code for a first portion of the channels and the secondary scrambling code for the remainder of the channels. 
     
     
       10. A secondary station for use in a radio communication system employing a code division multiple access technique,
 the secondary station comprising
 means for receiving spreaded data from a single primary station, the data encoded in separate and distinct portions by using at least one of a primary scrambling code and or a secondary scrambling code, wherein said data includes a slotted mode signal having a first portion encoded with the primary scrambling code and a second portion encoded with the secondary scrambling code, both portions being transmitted contemporaneously; 
 wherein the data is transmitted in slotted frames and non-slotted frames. 
 
 
     
     
       11. A communication station comprising:
 a transmitter for transmitting transmit data to a terminal; and   a receiver for receiving receive data from said terminal;   wherein one of said transmit data and receive data has a first portion and a second portion, said first portion being encoded with a primary scrambling code and said second portion being encoded with a secondary scrambling code; and   wherein said communication station is configured to one of transmit and receive both said first portion and said second portion contemporaneously.   
     
     
       12. The method as claimed in claim 1, further comprising the step of transmitting a slotted mode signal to the secondary station using a primary scrambling code for a first portion of the data and a secondary scrambling code for the remainder of the data, both portions being transmitted contemporaneously. 
     
     
       13. The primary station as claimed in claim 6, further comprising means for transmitting a slotted mode signal to the secondary station using the primary scrambling code for a first portion of the data and a secondary scrambling code for the remainder of the data, both portions being transmitted contemporaneously. 
     
     
       14. The radio communication system as claimed in claim 5, further comprising means for transmitting a slotted mode signal to the secondary station using the primary scrambling code for a first portion of the data and the secondary scrambling code for the remainder of the data, both portions being transmitted contemporaneously. 
     
     
       15. The secondary station as claimed in claim 10, wherein said data includes a slotted mode signal having a first portion encoded with the primary scrambling code and a second portion encoded with the secondary scrambling code, both portions being transmitted contemporaneously. 
     
     
       16. A method of operating a radio communication system employing a code division multiple access technique, the method comprising:
 enabling a primary station to transmit to a plurality of secondary stations, the primary station transmitting to a secondary station of the plurality of secondary stations data in slotted frames and non-slotted frames;   wherein data in the non-slotted frames is encoded with a first scrambling code, and at least a portion of the data is encoded in the slotted frames with a different scrambling code.   
     
     
       17. The method as claimed in claim 16, wherein in the slotted frames a first portion of the data is encoded with the first scrambling code and a second portion of the data is encoded with the different scrambling code, both portions being transmitted contemporaneously. 
     
     
       18. A primary station for use in a radio communication system employing a code division multiple access technique, the primary station comprising:
 means for transmitting to a plurality of secondary stations;   means for transmitting to a secondary station data in slotted frames and non-slotted frames; and   means for encoding data in the non-slotted frames with a first scrambling code and means for encoding at least a portion of the data in the slotted frames with a different scrambling code.   
     
     
       19. The primary station as claimed in claim 18, further comprising means for encoding a first portion of the data in the slotted frames with the first scrambling code and a second portion of the data in the slotted frames with the different scrambling code, both portions being transmitted contemporaneously. 
     
     
       20. A secondary station for use in a radio communication system employing a code division multiple access technique, the secondary station comprising:
 means for receiving data from a single primary station data in slotted frames and non-slotted frames;   means for receiving in the non-slotted frames data encoded with a first scrambling code; and   means for receiving data in the slotted frames at least a portion of which is encoded with a different scrambling code.   
     
     
       21. The secondary station as claimed in claim 20, further comprising means for receiving a first portion of the data in the slotted frames encoded with the first scrambling code and a second portion of the data in the slotted frames encoded with the different scrambling code, both portions being transmitted contemporaneously. 
     
     
       22. A primary station for use in a radio communication system employing a code division multiple access technique, the primary station comprising:
 a transceiver for transmitting data to a plurality of secondary stations in slotted frames and non-slotted frames;   wherein the data in the non-slotted frames is encoded with a first scrambling code and at least a portion of the data in the slotted frames is encoded with a different scrambling code.   
     
     
       23. The primary station as claimed in claim 22, wherein a first portion of the data in the slotted frames is encoded with the first scrambling code and wherein a second portion of the data in the slotted frames is encoded with the different scrambling code, both portions being transmitted contemporaneously. 
     
     
       24. A secondary station for use in a radio communication system employing a code division multiple access technique, the secondary station comprising:
 a transceiver for receiving data from a single primary station data in slotted frames and non-slotted frames;   wherein in the non-slotted frames the transceiver receives data encoded with a first scrambling code and in the slotted frames the transceiver receives data at least a portion of which is encoded with a different scrambling code.   
     
     
       25. The secondary station as claimed in claim 24, wherein a first portion of the data in the slotted frames is encoded with the first scrambling code and a second portion of the data in the slotted frames is encoded with the different scrambling code, both portions being transmitted contemporaneously and received by the transceiver.