Base station device and communication terminal device

• US 20040146017A1
• Filed: 10/30/2003
• Published: 07/29/2004
• Est. Priority Date: 03/01/2002
• Status: Abandoned Application

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Aoyama, Takahisa
• Application Number:
  US10/476,415
• Publication Number:
  US 20040146017A1
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04W 36/302 due to low signal strength

Abstract

The terminal information aggregation section (104) decides whether or not to carry out handover based on a CIR value sent from a communication terminal. When there are at least a predetermined number of communication terminals which should carry out handover, the IDLE period setting decision section (105) requests the setting of an IDLE period. The priority calculation section (106) calculates priority based on the CIR value. The scheduling section (107) carries out a setting and scheduling of the IDLE period. The data selection section (108) selects data to be sent to the scheduled communication terminal and the modulation/coding section (110) codes/modulates the selected data. The transmission ON/OFF section (111) performs control in such a way that data is not sent during the set IDLE period. In this way, according to a CDMA system in which data signals and common known signals are time-multiplexed and sent through the same channel, the present invention makes it possible to receive the common known signals with sufficient reception quality and thereby improve the accuracy of detecting other cells.

Claims

1. A CDMA-based base station apparatus using a shared channel, comprising:

a non-transmission period setting section that sets a non-transmission period during which transmissions of common known signals, control signals and data signals are stopped; and

a transmission control section that controls transmission in such a way that data transmission is stopped for only a period set by said non-transmission period setting section.

2. The base station apparatus according to claim 1, further comprising a quality decision section that keeps track of reception quality of the shared channel of the communication terminal apparatus and decides whether predetermined reception quality is satisfied or not, wherein when said quality decision section decides that the predetermined reception quality is not satisfied, said non-transmission period setting section sets a non-transmission period before the communication terminal apparatus which does not secure the predetermined reception quality starts handover.

3. The base station apparatus according to claim 2, wherein said non-transmission period setting section makes a threshold decision by comparing the number of communication terminal apparatuses which do not secure the predetermined reception quality with a predetermined threshold and sets a non-transmission period when the result of the threshold decision is equal to or greater than the threshold.

4. The base station apparatus according to claim 1, further comprising:

a non-transmission period setting information generation section that generates information for notifying the non-transmission period set by said non-transmission period setting section to said communication terminal apparatus; and

a transmission section that sends the information generated by said non-transmission period setting information generation section to said communication terminal apparatus.

5. The base station apparatus according to claim 1, further comprising a non-transmission request reception section that receives a signal requesting the setting of a non-transmission period from said communication terminal apparatus and requests said non-transmission period setting section to set a non-transmission period.

6. The base station apparatus according to claim 1, further comprising:

another cell information reception section that receives frame timing information of another adjacent cell; and

a frame timing control section that multiplexes the transmission timing of the other cell common known signal with the non-transmission period based on said frame timing information.

7. A communication terminal apparatus comprising:

another cell demodulation section that demodulates another cell signal within a non-transmission period set by a base station apparatus; and

another cell detection section that detects another cell based on said demodulated other cell signal,

wherein handover is carried out to said other cell detected within said non-transmission period.

8. The communication terminal apparatus according to claim 7, further comprising:

a non-transmission period setting information detection section that receives and detects non-transmission period setting information sent from the base station apparatus; and

another cell demodulation start decision section that decides the timing for starting demodulation of the other cell signal based on said non-transmission period setting information,

wherein said other cell signal demodulation section starts demodulation of the other cell signal at the demodulation start timing of said decided other cell signal.

9. The communication terminal apparatus according to claim 7, further comprising:

a reception quality measuring section that measures the reception quality of the shared channel sent from the base station apparatus;

a reception quality decision section that decides whether said measured reception quality satisfies predetermined reception quality or not;

a non-transmission period detection section that receives non-transmission period setting information sent from the base station apparatus and detects whether said non-transmission period has been set or not;

a non-transmission request signal generation section that generates a signal requesting the base station apparatus to set a non-transmission period when said reception quality does not satisfy the predetermined reception quality, said non-transmission period is not detected and said other cell detection section cannot detect the other cell;

a transmission section that sends the non-transmission request signal to the base station.

10. A base station control apparatus that controls a plurality of base station apparatuses, comprising:

a frame timing decision section that decides frame timings by shifting transmission timings of common known signals sent from the adjacent base station apparatuses based on position information of said plurality of base station apparatuses under control; and

a frame timing notification section that notifies said decided frame timings to said plurality of base station apparatuses under control.

11. A CDMA-based radio communication method using a shared channel, comprising the steps of:

setting a non-transmission period during which transmissions of common known signals, control signals and data signals are stopped; and

carrying out control in such a way that data transmission is stopped for only said non-transmission period set.