WIRELESS DEVICE

• US 20100248644A1
• Filed: 03/23/2010
• Published: 09/30/2010
• Est. Priority Date: 03/24/2009
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Infotechnology Center Co., Ltd. (Toyota Motor Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: OKADA, Hiroki, KISHI, Takahiko
• Granted Patent: US 8,768,285 B2
• Time in Patent Office: Days
• US Class Current: 455/68
• CPC Class Codes: H04B 1/3822 specially adapted for use in vehicles H04B1/3827 takes precedence
• CPC Class Codes: H04L 7/0008 Synchronisation information channels, e.g. clock distribution lines

Abstract

A wireless device includes a baseband unit and front-end units that are provided in individual housings. The baseband unit and the front-end units are connected to each other by wire. A transmitter for synchronization that converts a signal based on a reference clock into a radio signal and transmits the radio signal as a clock synchronization signal is provided in any one of the housings, and receivers for synchronization that receive the signal for the clock synchronization and PLLs that generate a clock synchronized with a reference clock signal which is obtained from the received clock synchronization signal are provided in the housings other than the housing having the transmitter provided therein. In order to simultaneously process a plurality of wireless devices having different symbol rates, it is preferable to provide the transmitter, the receiver, and the PLL for each reference clock.

Claims

1. A wireless device comprising:

a baseband unit; and

one or more front-end units,

wherein the baseband unit and the front-end units are provided in individual housings,

the baseband unit and the front-end units are connected to each other by wire,

a transmitter that converts a signal based on a reference clock into a radio signal and transmits the radio signal as a clock synchronization signal is provided in any one of the housings, and

receivers that receive the clock synchronization signal and PLLs that generate a clock synchronized with a reference clock signal which is obtained from the clock synchronization signal are provided in the housings other than the housing having the transmitter provided therein.

2. A wireless device according to claim 1,

wherein the wireless device performs communication using a plurality of wireless systems having different symbol rates at the same time and uses a plurality of different reference clocks, and

the transmitter, the receiver, and the PLL are provided for each reference clock.

3. A wireless device according to claim 1,

wherein the transmitter transmits the clock synchronization signal as a burst signal.

4. A wireless device according to claim 3,

wherein the transmitter performs carrier sensing before burst transmission.

5. A wireless device according to claim 1,

wherein the transmitter transmits the clock synchronization signal including identification information, and

the receiver determines whether the clock synchronization signal is received from a corresponding transmitter based on the identification information and updates the PLL when the clock synchronization signal is received from the corresponding transmitter.