Method access point device and peripheral for providing space diversity in a time division duplex wireless system

• US 6,088,337 A
• Filed: 10/20/1997
• Issued: 07/11/2000
• Est. Priority Date: 10/20/1997
• Status: Expired due to Term

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Kepler, James Frank, Cudak, Mark Conrad, Eastmond, Bruce Charles
• Primary Examiner(s): Vu, Huy D.
• Assistant Examiner(s): KWOH, JASPER C
• Application Number:
  US08/954,770
• Time in Patent Office: 995 Days
• Field of Search: 370/252, 370/280, 370/294, 714/758
• US Class Current: 370/280
• CPC Class Codes: H04B 7/0602 using antenna switching H04B7/0686 takes precedence; antenna beam directivity switching H01Q3/24
• CPC Class Codes: H04B 7/0604 with predefined switching scheme
• CPC Class Codes: H04B 7/0802 using antenna selection H04B7/0868 takes precedence; antenna beam directivity switching H01Q3/24
• CPC Class Codes: H04B 7/0822 according to predefined selection scheme
• CPC Class Codes: H04W 52/383 power control in peer-to-peer links

Abstract

A method, access point device and a plurality of peripheral devices provide for controlling a space diversity switch in a time division duplex system. The method includes: inputting data to a peripheral; generating a CRC₁ in a peripheral; transmitting the data and the CRC₁ ; receiving, by an access point device, the data with the CRC₁ ; extracting CRC₁ and generating CRC₂ from received data; determining whether CRC₁ and CRC₂ are equal and where CRC₁ and CRC₂ are equal, failing to generate a repeat request; where CRC₁ and CRC₂ are unequal, generating a repeat request; determining whether a number of requests=N; where the number of requests≠N, incrementing a counter and returning to receiving the data with the CRC₁ ; and where the number of requests=N, resetting the counter, changing an antenna state and returning to receiving, by an access point device, the data with the CRC₁.

Claims

1. A method for controlling a space diversity switch in a time division duplex system, comprising the steps of:

A) inputting data to a peripheral;

B) generating a first cyclic redundancy check CRC₁ in a peripheral;

C) transmitting the data and the CRC₁ by the peripheral;

D) receiving, by an access point device, the data with the CRC₁ ;

E) extracting CRC₁ from received data and generating a second cyclic redundancy check CRC₂ from received data;

F) determining whether CRC₁ and CRC₂ are equal; and

where CRC₁ and CRC₂ are equal, failing to generate a repeat request;

G) where CRC₁ and CRC₂ are unequal, generating a repeat request;

H) incrementing a counter;

I) determining whether a number of requests=N, wherein N is a predetermined integer, and where the number of requests≠

N, incrementing a counter and returning to step D; and

J) where the number of requests=N, resetting the counter, changing an antenna state and returning to step D.

2. An access point device for providing space diversity in a time division duplex system, comprising:

A) an access point device transceiver, coupled to receive access point device data input;

B) a checking unit, for transmitting and receiving time division duplex data, the checking unit, coupled to the access point device transceiver, for determining whether to generate a repeat request;

C) an antenna control unit, coupled to the checking unit, for changing antenna selection based on a predetermined scheme;

D) an antenna unit, coupled to the antenna control unit and a time division duplex switch, for communicating with a peripheral device;

wherein the access point device transceiver includes;

a transmitter, coupled to a data block format logic unit, for transmitting data;

the data block format logic unit, coupled to receive data from a peripheral device, for arranging data from the peripheral device in blocks;

a controller, coupled to receive repeat requests, the data block format logic unit and a data block unformat logic unit, for controlling the operation of the transceiver;

the data block unformat logic unit, coupled to a receiver, for stripping the data and a first CRC from the peripheral device out of the data block;

the receiver, coupled to a time division duplex switch, for receiving data from the peripheral device;

the time division duplex switch, coupled to the transmitter and receiver, for directing radio frequency signals to and from the access point device transceiver;

E) a CRC generation unit coupled to the data block format logic unit, for generating a CRC for the data received from the peripheral device;

wherein the checking unit includes;

a CRC₂ generation unit, coupled to the data block unformat logic unit, for generating a second CRC from the data received from the peripheral device; and

a CRC checking unit, coupled to the data block unformat logic unit and the CRC₂ generation unit, for comparing the first CRC and the second CRC and outputting a repeat request when the first CRC is unequal to the second CRC and incrementing an N-event counter of the antenna control unit.

3. The access point device of claim 2 wherein the antenna control unit is an N event counter coupled to receive repeat requests, for counting a number of repeat requests and a toggle flip-flop, coupled to the N event counter, for, when a number of repeat request events exceeds N, a predetermined integer, changing an antenna state.

4. The access point device of claim 2 wherein the checking unit includes:

A) a signal quality determining unit, coupled to the receiver, for generating a signal proportional to a received signal;

B) a transmission gate, coupled to the signal quality determining unit and the data block unformat logic unit, for sampling signal quality determining unit output during a data block; and

C) a comparator, coupled to the transmission gate, for determining a signal quality determining unit level and where the signal quality determining unit level is less than a predetermined threshold, changing an antenna state.

5. The access point device of claim 4 wherein the antenna control unit includes a toggle flip flop, coupled to the comparator, for, when a received signal level from the peripheral device falls below a predetermined threshold during a data block interval, changing the antenna state.

6. The access point device of claim 4 wherein the antenna unit is one of:

A) a selectable antenna; and

B) a phasing array.

7. A peripheral device for providing space diversity in a time division duplex system, comprising:

A) a peripheral device transceiver, coupled to receive device data input, an antenna, for transmitting and receiving time division duplex data, wherein the peripheral device transceiver comprises;

A1) a transmitter, coupled to a data block format logic unit, for transmitting data;

A2) the data block format logic unit, coupled to receive data from a peripheral, for arranging data from the peripheral in blocks;

A3) a controller, coupled to receive repeat requests, the data block format logic unit and a data block unformat logic unit, for controlling the operation of the peripheral device transceiver;

A4) the data block unformat logic unit, couple to a receiver, organizing a continuous stream of data into blocks having a predetermined number of bits and adding another predetermined number of control bits;

A5) the receiver, coupled to a time division duplex switch, for receiving data from an access point device;

A6) the time division duplex switch, coupled to the transmitter and receiver, for directing radio frequency signals to and from the peripheral device transceiver;

B) an antenna, coupled to the peripheral device transceiver, for communicating with an access point device;

C) a checking unit, coupled to the peripheral device transceiver, wherein the checking unit comprises;

a CRC generation unit, coupled to the data block unformat logic unit, for generating a cyclic redundancy code CRC from the data input; and

a CRC checking unit, coupled to the data block unformat logic unit and the CRC generation unit, for comparing the CRC generated by the CRC generation unit with a CRC sent by an access point transceiver for outputting a repeat request when the CRC generated by the CRC generation unit is unequal to the CRC sent by the access point transceiver.

8. The peripheral device of claim 7 further including a CRC₁ generation unit coupled to the data block format logic unit, for generating a CRC₁ for the data received from an access point device.

9. A method for controlling a space diversity switch in a time division duplex system, comprising the steps of:

A) inputting data to an access point device;

B) generating a first cyclic redundancy check CRC₁ in the access point device;

C) transmitting the data and the CRC₁ by the access point device;

D) receiving, by a peripheral device, the data with the CRC₁ ;

E) extracting CRC₁ from received data and generating a second cyclic redundancy check CRC₂ from received data;

F) determining whether CRC₁ and CRC₂ are equal, and where CRC₁ and CRC₂ are equal, transmitting an acknowledgment ACK;

G) where CRC₁ and CRC₂ are unequal, transmitting a negative acknowledgment NAK;

H) receiving the ACK/NAK at a receiver of the access point device;

I) determining, by the access point device, whether one of;

an ACK and a NAK was received;

J) where an ACK has been received, failing to generate a repeat request and where a NAK has been received, generating a repeat request by the access point device;

K) incrementing a counter;

L) determining whether a number of requests=N, N a predetermined integer and where the number of requests≠

N, returning to step C; and

M) where the number of requests=N, resetting the counter, changing an antenna state and returning to step C.