Processing uplink data transmissions in a heterogeneous wireless network

1. A method of facilitating operation of a base station in a cellular wireless communication system, comprising:

controlling a wireless device to wirelessly transmit, in a first time slot at a first position in a first transmission subframe, data over a first physical communication channel;

receiving, over a backhaul network connection that is different from the first physical communication channel, a control message, a first time period after the first time slot, from a microcell base station indicating whether or not the data was received correctly during the first time slot; and

transmitting, to the wireless device, over a second physical communication channel that is different from the first physical communication channel and the backhaul network connection, a response message in a second time slot that is a pre-determined time period after the first time slot, such that

i) when the control message is received prior to the second time slot, then the response message includes data reception information in the received control message and

ii) when the control message is not received prior to the second time slot, then the response message includes a dummy acknowledgement allowing the wireless device to continue operating in deterministic manner.

2. The method recited in claim 1 , further comprising:

controlling another wireless device to wirelessly transmit, when the control message is not received prior to the second time slot, in a second time slot at the first position in a second transmission subframe, data over the first physical communication channel.

3. The method recited in claim 1 , wherein the first physical communication channel comprises a physical uplink channel shared by the wireless device with other wireless devices in the cellular wireless communication system.

4. A base station apparatus operable in a cellular wireless communication system, comprising:

a uplink transmission scheduler that controls a user equipment to wirelessly transmit, in a first time slot at a first position in a first transmission subframe, data over a first physical communication channel;

a backhaul receiver that receives, over a backhaul network connection that is different from the first physical communication channel, a control message, in a first time period after the first time slot, from a microcell base station indicating whether or not the data was received correctly during the first time slot; and

a transmitter that transmits, to the wireless device, over a second physical communication channel that is different from the first physical communication channel and the backhaul network connection, a response message in a second time slot that is a pre-determined time period after the first time slot, such that

i) when the control message is received prior to the second time slot, then the response message includes data reception information in the received control message and

ii) when the control message is not received prior to the second time slot, then the response message includes a dummy acknowledgement allowing the wireless device to continue operating in deterministic manner.

5. The apparatus recited in claim 4 , wherein the uplink transmission scheduler controls another wireless device to wirelessly transmit, when the control message is not received prior to the second time slot, in a second time slot at the first position in a second transmission subframe, data over the first physical communication channel.

6. The apparatus recited in claim 4 , wherein the first physical communication channel comprises a physical uplink channel shared by the wireless device with other wireless devices in the cellular wireless communication system.

7. A method of operation of a wireless network node, comprising:

operating a wireless receiver to receive, in a first designated time slot, a first uplink transmission from a wireless device over a wireless network connection;

communicating, when the first uplink transmission is successfully received, an acknowledgement message (ACK) to a network server over a backhaul connection that is different from the wireless network connection,

otherwise, when the first uplink transmission is not successfully received, communicating a negative acknowledgement message (NACK) to the network server over the backhaul connection that is different from the wireless network connection; and

controlling the wireless network node to refrain from transmitting ACK or NACK messages over the wireless network connection.

8. The method recited in claim 7 , further comprising:

operating the wireless network node to transmit and receive wireless signals according to a schedule received from another wireless network node.

9. The method recited in claim 7 , wherein the backhaul connection is comprises a wired transmission medium.

10. A wireless network apparatus, comprising:

a wireless receiver that receives, in a first designated time slot, a first uplink transmission from a wireless device over a wireless network connection;

a backhaul transmitter that transmits, when the first uplink transmission is successfully received, an acknowledgement message (ACK) to a network server over a backhaul connection that is different from the wireless network connection,

otherwise, when the first uplink transmission is not successfully received, the backhaul transmitter transmits a negative acknowledgement message (NACK) to the network server over the backhaul connection that is different from the wireless network connection; and

a controller that controls the wireless network apparatus to refrain from transmitting ACK or NACK messages over the wireless network connection.

11. The apparatus recited in claim 10 , wherein the controller further operates the wireless network node to transmit and receive wireless signals according to a schedule received from another wireless network node.

12. A method of controlling uplink data transmission operation of a wireless device in a heterogeneous wireless network comprising a macro base station and a plurality of micro base stations, comprising:

instructing, from the macro base station, the wireless device to perform uplink data transmission in a first time slot over a wireless network connection, without attempting to receive the uplink data transmission at the macro base station;

performing reception of acknowledgement messages from at least some of the plurality of micro base stations over a backhaul connection that is different from the wireless network connection at least until earlier of receiving a positive or negative acknowledgement from a micro base station or expiration of a time period after the first time slot to facilitate a timely feedback for the uplink data transmission to the wireless device; and

transmitting, from the macro base station, the feedback to the wireless device based on the received acknowledgement messages over a broadcast physical channel.

13. The method recited in claim 12 , wherein the first time slot repetitively occurs at a fixed location in transmission subframes.

14. A macro base station for controlling uplink data transmission operation of a wireless device in a heterogeneous wireless network comprising the macro base station and a plurality of micro base stations, comprising:

an uplink transmission scheduler that instructs the wireless device to perform uplink data transmission in a first time slot over a wireless network connection, without attempting to receive the uplink data transmission at the macro base station;

a backhaul receiver that receives acknowledgement messages from at least some of the plurality of micro base stations over a backhaul connection that is different from the wireless network connection at least until earlier of receiving a positive or negative acknowledgement from a micro base station or expiration of a time period after the first time slot to facilitate a timely feedback for the uplink data transmission to the wireless device; and

a downlink transmitter that transmits the feedback from the macro base station to the wireless device based on the received acknowledgement messages over a broadcast physical channel.

15. The apparatus recited in claim 14 , wherein the uplink transmission scheduler further instructs the wireless device to perform new data transmissions using another physical channel.