Communication method and radio apparatus using the communication method
A control unit allocates sequentially a channel for use in data transmission and a channel for use in channel estimation used to acquire channel characteristics between a radio apparatus and another radio apparatus to be communicated with, to the another radio apparatus. A radio unit to an IF unit communicate with the another radio unit through the sequentially allocated data transmission channels, respectively. An acquisition unit acquires the traveling speed of the another radio apparatus in communication with the radio apparatus. A decision unit varies the frequency at which the channel for use in channel estimation is allocated, based on the traveling speed acquired.
1. A radio apparatus, comprising:
an allocation unit configured to sequentially allocate a channel for use in data transmission and a channel for use in channel estimation used to acquire channel characteristics between said radio apparatus and another radio apparatus to be communicated therewith, to the another radio apparatus;
a communication unit configured to communicate with the another radio unit through the data transmission channels sequentially allocated by said allocation unit, respectively; and
an acquisition unit configured to acquire a relative traveling speed between said radio apparatus and the another radio apparatus communicating in said communication unit,
wherein said communication unit varies the frequency at which the channel for use in channel estimation is allocated, based on the relative traveling speed acquired by said acquisition unit.
2. A radio apparatus according to claim 1 , wherein said communication unit defines a relation in response to an increase in traveling speed such that when the traveling speed is less than a threshold value, the frequency increases and such that when the traveling speed is greater than or equal to the threshold value, the frequency decreases, and
said communication unit determines the frequency based on the relation and the traveling speed acquired by said acquisition unit.
3. A radio apparatus according to claim 1 , wherein said communication unit varies the frequency of use of burst signal transmitted from the another radio apparatus to said radio apparatus, instead of the allocation of the channel for use in data transmission, according to the traveling speed acquired by said acquisition unit,
wherein the burst signal contains an estimation result of the channel characteristics.
4. A communication method, comprising:
allocating sequentially a channel for use in data transmission and a channel for use in channel estimation used to acquire channel characteristics between a radio apparatus and another radio apparatus to be communicated therewith, to the another radio apparatus;
communicating with the another radio unit through the data transmission channels sequentially allocated, respectively;
acquiring a relative traveling speed between the radio apparatus and the another radio apparatus communicating with the radio apparatus; and
varying the frequency at which the channel for use in channel estimation is allocated, based on the acquired relative traveling speed.