DE29711760U1 - Wireless connection device for a computer input / output device - Google Patents

Description

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ZEITLER & DICKEL" ' PATENT ATTORNEYS · EUROPEAN PATENT ATTORNEYS

PO BOX 26 02 51 TELEPHONE: 089/22 18 06 HERRNSTRASSE 15

D-80059 MUNICH FAX: 089/22 26 27 D-80539 MUNICH

6329 os

PRIMAX ELECTRONICS LTD.

6/F, No. 159, Kang Ning St.

Hsi Chih Town,

Taipei, Taiwan,

R.O.C.

Wireless connection device for a computer input

/Output device

The invention relates to a wireless connection device for a computer input/output device for transmitting data between a computer and a plurality of input devices, such as a keyboard, a mouse or a joystick or between a computer and a television screen for displaying an image on the television screen.

In the current information age, a computer has become an essential tool for almost all working life, both in the office and at home. A conventional personal computer (PC) design includes a main unit, a monitor, a number of peripherals and a number of _different types of input devices, such as a keyboard, mouse or joystick. The computer market is a highly competitive area of the business world. In order to make computers and related devices more competitive in the market, they are becoming smaller and contain more integrated functions. A key factor in making computer products more competitive is to make them easier to operate for the user.

easy and convenient. Traditionally, the computer input devices such as keyboard, mouse and joystick are connected to the computer via cables. This means that the user has to operate these devices while sitting right next to the computer, which is sometimes inconvenient when there is a distance between the user and the computer. To provide a solution to this problem, wireless input devices such as a wireless keyboard and a wireless mouse are already available in the market. These wireless input devices allow the user to operate the computer from a greater distance and also eliminate the need for tangled cables on the back of the computer.

However, the use of these wireless input devices results in the disadvantage that since each of the input devices is provided with its own radio device to transmit the special data signals to the computer, the computer is overloaded with various receiving devices installed thereon to receive the radio signals from the respective wireless input devices. In addition, mutual interference may occur between these wireless input devices, so that the operation of the computer may be adversely affected.

Currently, a personal computer is equipped with functions that can be integrated using various commercially available electronic components. For example,

3Q When playing video tapes, the PC must be connected to a television set in order to display the game or the image on the television monitor. Traditionally, this is achieved by installing a video card in a corresponding port on the PC in order to connect the PC to the television monitor via a cable. However, this can often be disadvantageous for the user when operating the computer in the case where the PC is in a corner of the

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room, while the TV monitor is at a greater distance from the PC. This disadvantage is usually a major factor in making a novice user unwilling to use the computer. 5

Accordingly, the invention is based on the object of providing a wireless connection device for a computer input/output device while avoiding the disadvantages outlined, which allows various input devices to transmit the input data signals to the computer by means of a radio connection, without having to establish a physical connection to the computer via a cable.

Furthermore, the connection device should have a simple structure so that the costs for using the computer can be reduced. In addition, the connection device should be designed in such a way that no mutual influence of the radio signals required for data transmission can occur.

Finally, the connection device should be able to be controlled via a plurality of switches in such a way that the computer can be operated in a simple manner and can perform certain programmed functions.

This object is achieved according to the invention by the features specified in the characterizing part of the main claim, whereby with regard to preferred embodiments of the connecting device according to the invention, reference is made to the features of the subclaims.

This provides a wireless connection device for a computer input/output device, or which is suitable for transmitting input data signals via a radio channel to a computer having a plurality of ports. According to a preferred embodiment

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In this embodiment, the wireless connection device comprises the following features, namely:

(a) a radio transmitter comprising:

(I) a first microprocessor connected to receive data signals from at least one input device for performing a predetermined processing operation on the received data signal to thereby generate a sequential bit stream,

(II) a modulator connected to said first microprocessor for modulating the sequential bit stream into a radio signal and

(III) a device for emitting the radio signal and

(b) a radio receiver installed on the computer with:

(I) a device for receiving the radio signal,

(II) a demodulator connected to the radio signal receiver for demodulating the received radio signal into a digital form

(III) a second microprocessor connected to the demodulator for performing a reverse processing operation on the digital form of the received radio signal to form the data signal in its original form which was generated by the input device, the second microprocessor then feeding the data signal to the corresponding port on the computer.

The radio transmission also includes an analogue/digital (A/D) converter connected between the first microprocessor and the first input device, provided that the input device is of a type that

or a control signal is generated in analog form to convert the analog output of the input device into a digital form.

The radio receiver further comprises a D/A converter connected between the second microprocessor and one of the ports of the computer, provided that the port is of a type capable of receiving analog signals, in order to convert the digital output of the second microprocessor into an analog form.

In order to enable quick and convenient operation of certain programmed functions, the radio transmitter comprises at least one button switch which, when depressed, is capable of actuating the first microprocessor to emit a programmed function driver signal via the radio channel to the computer so that the computer can execute a correspondingly programmed function.

According to another embodiment of the invention, the wireless connection device according to the invention is suitable for data communication between a computer having a plurality of ports and a television set, wherein at least one input device is used to transmit a data signal to the computer via the radio channel, while the television set is used to display a display thereon when a video control signal is received from the computer. The wireless connection device according to this embodiment comprises the following features, namely:

3Q (a) a first radio transmitter comprising:

(I) a first microprocessor connected to receive a data signal from at least one input device for performing a predetermined format conversion operation on the received data signal to generate a sequential bit stream,

(II) a modulator connected to the first microprocessor for modulating the sequential

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bit stream into a first radio signal and

(III) a device for emitting the first radio signal,

(b) a first radio receiver installed on the computer comprising:

(I) a device for receiving this radio signal,

(II) a demodulator connected to the first radio

signal receiver is connected to demodulate the received first radio signal into a digital form and

(III) a second microprocessor connected to the demodulator for performing a reverse format conversion operation on the digital form of the received radio signal to obtain the original form of the data signal generated by the input device, the second microprocessor then transmitting the data signal to the corresponding port of the computer,

(c) a second radio transmitter connected to the computer

is installed with:

(I) a modulator connected to the computer for modulating the video control signal from the computer into a second radio signal and

(II) means for emitting the second radio signal and

(d) a second radio receiver installed on the television system, comprising:

(I) a device for receiving the second radio signal and

(II) a demodulator connected to the second radio signal receiver for demodulating the received second radio signal into the form of the original video control signal generated by the computer, the video control signal being used to

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To control the television system for video playback.

The wireless connection device performs the step of appending an identification code to the data signal generated by the input device, the identification code being uniquely associated with that input device, while then at the receiving end the wireless connection device performs a reverse format conversion process on the digital form of the received radio signal to obtain the original form of the data signal generated by the input device, the identification code appended to the data signal indicating the destination of the data signal. In accordance with the identification code the wireless connection device transmits the data signal to the corresponding port of the computer.

Further advantages, details and essential features of the invention emerge from the following description of various embodiments of the invention with reference to the accompanying drawings. In particular:

Fig. 1 is a schematic diagram of a preferred embodiment of the wireless

Connecting device installed between a PC and a plurality of input devices and between the PC and a television system,

Fig. 2 is a schematic block diagram of a radio transmitter

mitters of the wireless connection device according to the invention, which is connected to the input devices,

Fig. 3 is a flow chart showing the operational steps performed by the radio transmitter

according to Fig. 2,

Fig. 4 is a schematic block diagram of a radio receiver of the wireless connection device according to the invention installed on the PC

is and

Fig. 5 is a flow chart showing the operational steps performed by the radio receiver of Fig. 4.

Fig. 1 is a schematic diagram showing a practical application of the connection device according to the invention for data communication between a personal computer (PC) 30 and a plurality of input devices, such as a keyboard 20A, a mouse 20B, and a joystick 20C, as well as between the PC 30 and a television (TV) 40. The wireless connection device according to this embodiment comprises a first radio transmitter 10 which is physically connected to the input devices 20A, 20B, 20C, a first radio receiver 50 which is installed on the PC 30 and has a radio channel between the first radio transmitter 10, a second radio transmitter 60 which is installed on the PC 30 for receiving a video control signal from the PC 30, and a second radio receiver 70 which is installed on the TV 40 and has a radio channel to the second radio transmitter 60 on the PC 30. The radio transmitters 10, 60 are equipped with devices for emitting radio signals, such as antennas 16, 62.

3Q, while the radio receivers 50, 70 are provided with radio signal receiving devices, such as the antennas 52, 72.

The first radio transmitter 10 comprises a plurality of anodes 12A, 12B, 12C, which are specifically designed for connecting the first radio transmitter 10 to certain input devices. In this embodiment, for example,

the first port 12A is specifically designed for connection to a keyboard 2OA, the second port 12B is specifically designed for connection to a mouse 2OB and the third port 12C is specifically designed for connection to a joystick 2OC. These ports 12A, 12B, 12C are similar in structure to a conventional keyboard port, mouse port or game control port, as are usually provided on the back of a personal computer.

The first radio transmitter 10 is specifically designed to transmit all input data and/or control signals (collectively referred to hereinafter as data signals) generated by the keyboard 2OA, the mouse 2OB and the joystick 2OC over a single radio channel to the PC 30. When any data is received from these input devices, the first radio transmitter 10 performs a format conversion operation on the data signal as described below.

For example, if the first radio transmitter 10 receives a 5-byte keyboard signal and a 3-byte mouse signal, they are combined as follows:

K1 K2 K3 K4 K5 M1 M2 M3

where K1 - K5 represents the five bytes of each keyboard signal and

M1 - M3 represent the three bytes of each mouse signal.

For example, in the format conversion process, each byte of a data signal is appended to a specific identification code that is uniquely associated with the input device that generates that data signal. In this embodiment, the identification code is a 3-bit code. For example, the code [001] is used as an identification code.

[010] is assigned as an identification code to the keyboard and [010] is assigned as an identification code to the mouse. A sequential bit stream is thus formed by appending the corresponding identification codes to all bytes of the data signals generated by the input devices, as illustrated for example below:

(001K1) (001K2) (001K3) (001K4) (001K5) (010M1) (010M2) (010M3).

The format conversion process described above is merely exemplary and is not intended to limit the scope of the invention. Other format conversion techniques are also suitable, such as time division multiplexing may be used to combine the data signals from the various input devices so that they can be transmitted over a single channel (e.g., the radio channel between the first radio transmitter 10 and the first radio receiver 50). The formatted bit stream is then converted by conventional modulating means into a modulated radio signal suitable for transmission by the antenna 16 and subsequent reception by the PC 30. The techniques involved in radio transmission and reception by the antenna 16 on the first radio transmitter to the antenna 52 of the first radio receiver 50 are conventional and need not be described in more detail here.

At the PC 30, the radio signal transmitted by the first radio transmitter 10 is received by the antenna 52 through the first

2Q radio receiver 50 on the PC 30. In the first radio receiver 50, the received radio signal is demodulated into digital form by means of a conventional demodulation device. The first radio receiver 50 then performs a reverse format conversion process on the digital form of the

_£. received radio signal in order to obtain the original form of the data signals, which can be keyboard signals, mouse signals or joystick signals, which

generated by the input devices 2OA, 2OB or 2OC. These data signals are then transmitted from the first radio receiver 50 to the PC 30, which then carries out the corresponding function depending on the received data signals.

For example, through the reverse format conversion process in the first radio receiver 50, the original form of the sequential bit stream formed in the first radio transmitter 10 is obtained as follows:

(001K1) (001K2) (001K3) (001K4) (001K5) (010M1) (010M2) (010M3)

When the PC 30 receives this sequential bit stream, it examines the first three bits in each segment to determine the source of the associated byte. For example, in the first five segments received, the first three bits in each segment are 001, which is recognized as the identification code for the keyboard, and in the next three segments, the first three bits in each segment are 010, which is recognized as the identification code for the mouse. Accordingly, the PC 30 takes the first five bytes K1, K2, K3, K4 and K5 as the keyboard signal and the first three bytes M1, M2 and M3 as the mouse signal, with the keyboard signal then being applied to the keyboard port on the PC 30, while the mouse signal is applied to the mouse port thereon. The PC 30 then processes these signals using conventional means to perform the appropriate functions.

The above-described reverse format conversion process, which is performed by the first radio receiver 50, is then used to form the original form of the data signal which was generated by the input device 20A, 20B or 20C. The above-described example of the conversion process is merely exemplary and is not intended to limit the scope of the invention.

Fig. 2 is a schematic block diagram of the first radio transmitter 10 used in the wireless connection device according to the invention, while Fig. 3 is a flow chart of the operational steps performed by the first radio transmitter 10 according to Fig. 2.

Referring first to Fig. 2, the first radio transmitter 10 includes a microprocessor 210, an analog-to-digital (A/D) converter 220, a modulator 230 and a radio signal emitter including the antenna 16. The first radio transmitter 10 receives signals from the input devices such as a keyboard 2OA, a mouse 2OB, a game control port 2OC, a first serial communication port COM1 2OD, a second serial communication port COM2 2OE and a parallel port PAR 2OF. Since the signals coming from the joystick connected to the game control port 2OC are analog, the output of the game control port 20C is first converted by the A/D converter 220 into a digital form before being transmitted to the microprocessor 210. The microprocessor 210 is then used to perform the aforementioned format conversion process on the data signals received from the input devices such as the keyboard 2OA, the mouse 20B, the game control port 2OC, the COM1 port 2OD, the COM2 port 2OE and the PAR port 20F. The sequential bit stream output from the microprocessor 210 is then modulated by the modulator 230 into a radio signal which is then transmitted via the antenna 16.

Fig. 3 shows the operating steps performed by the

or microprocessor 210 within the first radio transmitter 10 according to Fig. 2. In the first step 300, the microprocessor 210 is started. In the next

In step 310, the microprocessor 210 scans the ports 12A, 12B, 12C, 12D, 12E, 12F to check if any of them are receiving data signals from the associated input devices. In step 320, the microprocessor 210 checks if any data signals are being received from the input devices. If NO, the process goes to step 340. If YES, the process goes to step 330, according to which the received data signals are converted into a sequential bit stream by a predefined format conversion process as described above. Thereafter, the process goes to step 340, in which the microprocessor 210 checks if there is output data. If NO, the process returns to step 310. If YES, the process goes to step 350 in which the output data is modulated into a radio signal which is radiated via the antenna 16.

Fig. 4 is a schematic block diagram of the first radio receiver 50 used in the wireless connection device according to the invention, and Fig. 5 is a flow chart showing the operational steps performed by the first radio receiver 50 according to Fig. 4.

As shown in Fig. 4, the first radio receiver 50 on the PC 30 includes a microprocessor 410, a demodulator 420, a digital/analog converter 430 and a radio wave receiving device, such as the antenna 52. In addition, the first radio receiver 50 includes

on a plurality of output terminals, each connected to the keyboard terminal 3OA, the mouse terminal 3OB, the game controller terminal 3OC, the COM1 terminal 3OD, the COM2 terminal 3OE and the PAR terminal 30F, which are typical standard PC 30 terminals.

The antenna 52 receives and transmits the radio signals to the demodulator 420, which demodulates the received radio signal.

into a digital form representing the original form of the sequential bit stream generated by the microprocessor 210 in the first radio transmitter 10. This sequential bit stream is then transmitted to the microprocessor 410. The microprocessor 410 performs a reverse format conversion operation on this sequential bit stream so as to obtain the original form of the data signals received by the first radio transmitter 10 via the terminals 12A, 12B, 12C, 12D, 12E, 12F. The microprocessor 410 then applies the various segments of the sequential bit stream to one of the terminals 3OA, 3OB, 3OC, 3OD, 30E, 30F on the PC 30 depending on the identification codes of those segments. Since the game control port 3OC only accepts analog signals, the D/A converter 430 is connected between the game control port 3OC and the associated output port of the microprocessor 410 to convert the digital output of the microprocessor 410 into an analog form prior to transmission to the game control port 3OC.

Fig. 5 is a flow chart of the operational steps performed by the microprocessor 410 in the first radio receiver 50 as shown in Fig. 4. In the first step 500, the microprocessor 410 is started. In the next step 510, the microprocessor 410 is switched to a standby state to receive data. Then, in step 520, the microprocessor 410 checks whether any data has been received. If NO, the process goes back to step 510. If YES, the process goes to

₃ q Step 530, in which the microprocessor 410 performs a reverse format conversion operation on the received data and then determines the assignment of the converted data. Next, in step 540, the microprocessor 410 outputs the converted data and transmits it to a particular port 3OA, 3OB, 3OC, 3OD, 3OE, 30F.

It is an advantage of the invention over the prior art

Technology that the input devices such as keyboard, mouse and joystick, which were traditionally connected to the PC via cables, can now all be brought together via the wireless connection facility so that the data signals from these input devices can all be transmitted to the PC via a single radio channel. This allows the user to use the input devices to transmit input signals to the PC without the need for a physical connection of the input devices to the PC via tangled and interfering cables, while also allowing the user to operate the PC at a distance away from the main unit of the PC.

Referring again to Fig. 1, another feature of the invention is that the first radio transmitter 10 can be provided with a plurality of push buttons 14 so that the user can initiate certain programmed functions built into the microprocessor 210. When any of the programmed functions, such as accessing the Internet or requesting to read email, is desired, the user can press the appropriate push button switch on the first radio transmitter 10 to initiate a drive signal. The drive signal is then transmitted over the radio channel to the PC 30 to command the PC 30 to perform the desired programmed functions. This allows the user to easily cause the PC 30 to perform some frequently or routinely used functions.

Furthermore, the invention allows signal transmission between the PC 30 and a video device, such as a TV system 40. As shown in Fig. 1, a second radio transmitter 60 with an antenna 62 is installed on the PC 30, while a second radio receiver 70 with an antenna 72 is installed on the TV system 40. The second radio transmitter 60 is connected in such a way that it is a

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Video control signal from the PC 30. This video control signal is converted by conventional modulation methods into a radio signal which is emitted via the antenna 62. At the end of the recording, the radio signal is received via the antenna 72 of the second radio receiver 70. The second radio receiver 30 then demodulates the received radio signal by conventional demodulation methods so that the original form of the video control signal generated by the PC 30 is retained. This video control signal is then fed to the TV system 40 for image reproduction by the TV system 40.

In the above arrangement, the PC 30 can not only display images on its own monitor but also output them via the TV system 40. This feature allows, for example, the user to display video games via the TV system 40, or it allows a computer teacher to operate the computer while the computer displays a display on a large TV screen nearby for the purpose of demonstrating the use of software to an audience.

According to other different embodiments, the first radio transmitter 10 can be combined integrally with the input devices, such as keyboard, mouse and joystick. Furthermore, remote control functions of the TV system 40 can be integrated into the first radio transmitter 10, so that the TV system 40 can be remotely controlled by using the first radio transmitter 10.

In summary, a wireless connection device for a computer input/output device is provided for several input devices, such as a keyboard, a mouse or a joystick, to transmit input data and control signals to the computer via a radio device. In particular, this wireless connection device allows the connection of several input devices to the computer via a

single radio channel. The wireless connection device comprises a radio transmitter capable of receiving data signals from the input device and appending thereto a predetermined identification code that uniquely associates the input device with these data signals and then modulates these data signals into a radio signal, which is then transmitted. On the computer side, a radio receiver is installed to receive and demodulate the radio signal into a digital form. The radio receiver then performs a reverse format conversion process to obtain the original form of the data signal from the corresponding input device and the appended identification code. According to this identification code, the wireless connection device transmits the data signal to the corresponding port on the computer. In addition, the wireless connection device comprises another group of radio transmitters and receivers installed on the computer and a television set. This makes it possible for a video control signal to be transmitted from the computer to the television system via another radio signal in order to display a display generated by the computer on the television system.

It should be expressly stated again at this point that the foregoing description is merely an exemplary one and that various changes and modifications are possible without departing from the scope of the invention.

Claims (16)

6329 os Protection claims 5 1. A wireless connection device for a computer input/output device to a computer having multiple ports, characterized by: a radio transmitter (10) with: a first microprocessor (210) connected to receive a data signal from at least one input device (2OA, 2OB, 20C) and to carry out a predetermined format conversion process on the received signal to form a sequential bit stream, a modulator (230) connected to the first microprocessor (210) for modulating the sequential bit stream into a radio signal and a device (16) for emitting the radio signal and a radio receiver (50) installed on the computer (30) with: a device (52) for receiving the radio signal, a demodulator (420) connected to the radio receiving device (52) for demodulating the received radio signal into a digital form and a second microprocessor (410) connected to the 3Q demodulator (420) is connected for performing a reverse format conversion process on the digital form of the received radio signal to provide the original form of the signal generated by the input device (20A, 20B, 20C), the second microprocessor (410) feeding the data signal to the corresponding port (12A, 12B, 12C) of the computer (30). · 2. Wireless connection device according to claim 1, characterized in that the radio transmitter (10) further comprises an analog/digital converter (220) which is connected between the first microprocessor (210) and at least one input device (20A, 20B, 20C), wherein at least one input device is of the type which generates a control signal in analog form for converting the analog output of the input device into a digital form. 3. Wireless connection device according to one of claims 1 or 2, characterized in that the radio receiver (50) further comprises a digital/analog converter (430) connected between the second microprocessor (410) and one of the ports (12A, 12B, 12C) of the computer (30), the port being of the type that receives analog signals for converting the digital output of the second microprocessor (410) into an analog form. 4. Wireless connection device according to one of the preceding claims, characterized in that the radio transmitter (10) comprises at least one button switch (14) which, when pressed down, is able to activate the first microprocessor (210) in such a way that a driver signal with a programmed function can be transmitted to the computer via the radio channel, which causes the computer to perform the correspondingly programmed function. 5. Wireless connection device according to claim 1, characterized in that the input device is a keyboard 3Q (20A). 6. Wireless connection device according to claim 1, characterized in that the input device is a mouse (20B). 7. Wireless connection device according to claim 1, characterized in that the input device is a joystick • * (20C). 8. Wireless connection device according to claim 1, characterized in that the data signal can be received via a serial communication connection (2OD, 20E). 9. Wireless connection device according to claim 1, characterized in that the data signal can be received via a parallel connection (20F). 10. Wireless connection device for data communication between a computer with a plurality of connections, at least one input device and a television system, wherein at least one input device can be used to transmit a data signal to the computer via a radio channel and a display can be reproduced via the television system, upon receipt of a radio signal received by the computer,
marked by: a first radio transmitter (10) with: a first microprocessor (210) connected to receive the data signal from at least one input device (2OA, 2OB, 20C) and perform a predetermined format conversion process on the received data signal for generating a sequential bit stream, a modulator (230) connected to the first microprocessor (210) for modulating the sequential bit stream into a first radio signal and a device (16) for emitting the first radio signal, a first radio receiver (50) installed on the computer (30), with: a device (52) for receiving the first radio signal, a demodulator (420) connected to the first radio signal receiver for demodulating the received captured first radio signal into a digital form and a second microprocessor connected to the demodulator (420) for performing a reverse format conversion operation on the digital form of the received radio signal to produce the original form of the data signal generated by the input device, the second microprocessor supplying the data signal to the corresponding port on the computer, a second radio transmitter (60) installed on the computer (30), comprising: a modulator connected to the computer (30) for modulating the video control signal from the computer into a second radio signal and a device (62) for emitting the second radio signal and a second radio receiver (70) installed on the television system (40), with: a device (72) for receiving the radio signal and a demodulator connected to the second radio receiver (70) for demodulating the received second radio signal into the form of the original video control signal generated by the computer, the video control signal being usable for controlling playback by the television system (40). 11. Wireless connection device according to claim 10, 3Q characterized in that the first radio transmitter (10) comprises an analog/digital converter which is connected between the first microprocessor (210) and at least one input device (20A, 20B, 20C), of which at least one is of the type which generates a control signal in analog form for converting the analog output of the input device into a digital form. PRIMAX ELECTRONICS LTD. 6329 I/Os 19 September 1997 12. Wireless connection device according to claim 11, characterized in that the first radio receiver comprises a digital/analog converter which is connected between the second microprocessor (410) and one of the ports (12A, 12B, 12C) of the computer (30), the port being of the type which receives analog signals, for converting the digital output of the second microprocessor (40) into w an analogous form. 13. Wireless connection device according to claim 10, characterized in that the first radio transmitter (10) comprises at least one button switch (14) which, when pressed down, is able to optimize the first microprocessor in such a way that it sends a driver signal with a programmed function to the computer via the radio channel. via which a correspondingly programmed function can be executed. 14. Wireless connection device according to claim 10, characterized in that it is connected to at least two input devices, whereby the data signals generated by the respective input devices are provided with different identification codes. 15. Wireless connection device according to claim 10, characterized in that the data signal consists of a number of bytes, each byte being provided with an identification code comprising a predetermined number of bits. 16. Wireless connection device according to one of the preceding claims, characterized in that the Radio transmitter comprising a microprocessor connected to receive the data signal from at least one input device for performing a predetermined format conversion process on the received data signal for generating a sequential bit stream, and a modulator connected to the microprocessor for modulating the sequential bit stream into a radio signal.