TECHNICAL AREA The present invention concerns modular structures for housing equipment. In particular it concerns a modular structure or cabinet to enclose electronic equipment such as a radio base station for a telephone system.

TECHNICAL BACKGROUND It is common for industrial electronic equipment to be housed in an enclosing structure out-of-doors to protect it from weather and intrusion or interference from unauthorised persons. It is also increasingly common to locate electronic equipment inside a room or other space of an existing building such that it is enclosed inside some type of housing.

Telephone systems using radio transmitters for systems such as GSM and UMTS require a series of locally located stations distributed in a region. The local stations carry out the functions of cellular stations, repeater stations, base stations and the like.

However placement of electronic equipment such as a radio base station for a telephone system in an existing building has technical requirements. Generally an enclosure shall be air tight to hinder ingress of dust, dirt etc and leakage of electromagnetic radiation from the equipment. However, electronic equipment usually requires cooling, either by a passive ventilation system or an active cooling system.

Space in an existing building is not always maintained at ordinary room temperature. Roof spaces, attics, may be unheated and cellar and basement spaces may be unheated and un-ventilated. Providing a housing or enclosure for electronic equipment in placed in an

existing building can require the building of a room built specially for the purpose. Such custom built rooms or equivalent housings are very expensive and time consuming to provide. In addition it may be difficult to gain access to an existing space such as a roof space where an enclosure or custom room is required. Additionally, once constructed, a custom built room or other enclosure is expensive to modify if requirements change.

There are existing pre-fabricated enclosures, housings and containers available on the market to house equipment out-of- doors. However, access to spaces in existing buildings, such as an attic space, roof space, crawl space or cellar tends to be restricted. It is difficult or expensive or both to introduce structures based on prefabricated containers and the like into such spaces in an existing building.

SUMMARY OF THE INVENTION.

Embodiments of the present invention aim to address one or several of the above mentioned problems. According to one aspect of the invention a modular structure is provided to enclose and house electronic equipment such as a radio base station for a telephone system network in a space inside an existing building.

According to another aspect of the invention a method is provided for providing and assembling an enclosure as a modular structure.

The main advantage of the invention is that the modular cabinet - may be assembled in the required space without special training, - may be changed in size or shape using the modular components, -provides the requirements of an enclosure such as excluding dust, keeping people out, -provides the requirements of an electrical enclosure. The largest item is a maximum 1.1 metre wide panel ensuring easy access in

existing building doorways and stairways. The modular panels are relatively light in weight.

The modular cabinet may easily include air conditioning and or heating/cooling equipment as necessary to provide desired operating conditions for the enclosed electronic equipment.

The present invention provides a way to permit rapid and low cost installation of equipment such as radio base stations for telephone systems and mobile telephone systems by putting them in existing buildings.

BRIEF DESCRIPTION OF THE FIGURES A more complete understanding of the method and system of the present invention may be had by reference to the following detailed description when taken in conjunction with the accompanying drawing wherein: Figure 1 shows a diagram of front elevation for a modular enclosure according to an embodiment of the invention Figure 2 shows a plan view of the modular enclosure according to an embodiment of the present invention; Figure 3 shows an exploded plan view of the modular enclosure according to an embodiment of the present invention; Figure 4 shows a plan view for an elongated configuration of the modular enclosure according to an embodiment of the present invention; Figure 5 shows a front elevation of the elongated configuration of Figure 4;

Figure 6 shows a plan view of a deepened configuration of the modular enclosure according to an embodiment of the present invention; Figure 7 shows a plan view of a side wall panel in part cut-away detail showing a locking device.

Figure 8a shows a plan view of two side wall panels and a roof element fastened together with the locking device, and Figure 8b is a zoom out of Figure 8a showing a location of the locking device in a wall side panel.

DESCRIPTION OF EMBODIMENTS Figure 1 shows a modular cabinet 1, side wall panels 2,3, and 4, and a side view of two end wall panels 8,9 in which only the panel edges are visible. A roof part 10 is indicated. Cabinets 11, 12,13 are shown inside modular cabinet 1.

Figure 2 shows a view from above of modular cabinet 1, with side wall panels 2, 3,4 and 5,6, 7 making up two side walls. Two end walls 8,9 are shown. Cabinets 11, 12, 13 are once again shown inside modular cabinet 1, and a door lla is shown as attached to cabinet 11.

Figure 3 shows a dimension D, the outside width of an end wall panel 8,9. The dimension D is the maximum width of the widest type of panel, typically 1100 mm i. e. 1. 1 metres wide. The end wall panel may therefore be carried on its side through a standard doorway with ease.

The modular cabinet 1 consists of side walls made up of identical side wall panels 2-7, and substantially identical end wall panels 8,9. The modular cabinet houses electrical equipment, shown here as electrical cabinets 11-13. There is room inside modular cabinet

1 to open a door such as lla to gain access inside each electrical equipment cabinet 11-13.

Figure 7 shows a part cut-away detail of a locking mechanism 15 located in a side wall panel such as panel 2 of figures 1-6. A first position A, a second position B, a depiction of hook 21a in position A and a depiction of the same hook as hook 21b in second position B. A lock mechanism head 22 is shown. A slot 23 is indicated in a panel adjacent to a first panel in which the locking device 15 is located.

The side wall panels 2-7 are joined to one another using a locking device, preferably a built-in lock such as locking mechanism 15.

The same mechanism is used to join the end wall panels 8,9 to the side wall panels. Referring to figure 7, two side wall panels such as 2,3 are arranged in position beside each other. Using a technician's key (not shown) a telephone company person (or an electrician, for example) fastens two adjacent panels together by rotating the hook part of the lock 15 through 90 degrees from position A to position B. The hook 21a moves through a quarter turn, passing through a slot 23 or other cut out in the edge of the adjacent side wall panel. It can be seen from Figure 1 that a side wall panel such as panel 2 is joined by a lock to side wall panel 3, and also to roof element 10, end wall panel 8, and a floor element (not shown in detail).

It follows then that the telephone company person then later gains access to the inside of the modular cabinet, to get to the electronic equipment in cabinets 11-13, by unlocking each of the locks around the periphery of a side wall panel such as panel 2.

The panel is then removed. When finished, the telephone company person replaces and re-locks the panel in place.

The positive mechanical engagement of the rotating hook or latch 21 mechanism used throughout the cabinet also has good mechanical properties under, for example, earthquake conditions. The locked

latch does not lock the panels in a rigid way, not as compared, for example, to welded joints. A degree of movement is permitted by such a lock under imposed loads. Thus the panels will remain locked together following an earthquake, satisfying such requirements for tolerance of such problems.

Figure 4 and Figure 5 shows an modular cabinet that has been extended in one direction, and has more side wall panels than the configuration shown in Figures 1 and 2. In figure 5 a cable tray 16 is shown, which may be any kind of cable ladder, cable frame or tray. The cable tray is preferably mounted slung from the roof element 10 and clear of the electrical cabinets 11-13.

The panels are preferably constructed from a sandwich construction, consisting of an outer skin of painted steel plate or sheet, preferably around 1.5 mm thick, placed around an inner core. The inner solid core is best formed from a composite or polymeric based material. One such suitable core material is a board of expanded polystyrene sheet of around 40mm in thickness.

This material and thickness confers a degree of strength and a large degree of soundproofing and heat insulation on the panel.

Alternative materials for the core include expanded polyurethane foam.

End wall panels 8,9 are pre-prepared with added means (not shown) to receive ventilation inlets, outlets, grills etc. , to attach a cooler or chiller and with salable inlets for cable entry/exit to/from the modular cabinet.

The floor (not shown in detail) may be a single skin sheet or plate. Alternatively a reinforced floor including beams or trusses to distribute weight between floor elements and beam elements may be used.

In the best use of the invention the panels are delivered to site in packed as one or more flat-packs. The side wall panels can be manufactured to any size from 0.61m wide and up to 2. lm or more

wide. The end wall panels are as previously mentioned advantageously l. Im wide. A suitable height for the panels is 2.15m.

The panels are best assembled in a substantially airtight manner.

In addition a high degree of electromagnetic leakage in or out is prevented by providing a labyrinth cross section (not shown) in the steel edges of the panels. Upon fastening the panels together with the locking mechanism 15, the edges of the panels are drawn tightly together and the labyrinth profiles ensure that no radiation may pass in or out of the joint. The degree of EMC (Electro Magnetic Compatibility) or EMI (Electro Magnetic Interference) shielding required varies with the service conditions. When performance to, for example MIL-STD-285 is required, extra rubber or elastomeric sealing strips or gaskets may be included in the panel joints.

Figure 6 shows a configuration of the modular cabinet 1 in which two end wall panels 8, 8'and 9, 9'are joined to each other and arranged as end walls at each end of the cabinet. The arrows demonstrate that access may be gained to equipment from two sides of the modular cabinet.

The present invention is advantageously used to house radio base station units for a telephone system in a space in an existing building. The telephone system may be of an advanced type known as a 3G (Third generation) system such as UMTS or similar. The telephone system may as well be an existing type such as GSM or any other known mobile system or cellular system.

In other uses of the present invention include enclosing any equipment that requires enclosure because of noise, for example compressors, air conditioning equipment, because of warmth or cold in an unheated/un-conditioned space, or to prevent unauthorised interference or tampering. Computing equipment such as computer

data servers or web servers may also be enclosed in a structure according to the present invention.

It is also noted that while the above describes exemplifying embodiments of the invention, there are several variations and modifications which may be made to the disclosed solution without departing from the scope of the present invention as defined in the appended claims.